Hydroids (Cnidaria, Hydrozoa) of the Danish expedition to

HYDROIDS OF THE DANISH EXPEDITION TO THE KEI ISLANDS 

Hydroids (Cnidaria, Hydrozoa) of the Danish expedition 

to the Kei Islands 

PETER SCHUCHERT 

Steenstrupia 

INTRODUCTION 

Steenstrupia 27(2): 137-256. 

137 

Schuchert, P. Hydroids (Cnidaria, Hydrozoa) of the Danish expedition to the Kei Islands. – 

Steenstrupia 27 (2): 137–256. Copenhagen, Denmark, May 2003 (for 2001). ISSN 0375-2909. 

This paper reports upon the marine athecate and thecate hydroids collected by the Danish expedition 

to the Kei Islands (Indonesia) in 1922. Concomitantly, the historic collection of hydroids from the 

Moluccas made by C. Pictet and M. Bedot in 1890 was revised. The family Tubidendridae Nutting, 

1905 is recognized as valid and its diagnosis emended. Taxonomic problems with the genera 

Campalecium and Mitrocomium are discussed. The new species Cladocarpus keiensis is described. 

Ectopleura pacifica Thornely, 1900 is considered to be a subjective junior synonym of Tubularia 

viridis Pictet, 1893. Acryptolaria rectangularis (Jarvis, 1922) is removed from the synonymy of 

Acryptolaria angulata (Bale, 1914). Gymnangium unjinense Watson, 2000 is recognized as a 

subjective synonym of Lytocarpia orientalis (Billard, 1908). The following 15 species are new 

records for Indonesian waters: Hydractinia granulata Hirohito, 1988; Balella mirabilis (Nutting, 

1905); Garveia clevelandensis Pennycuik, 1959; Eudendrium kirkpatricki Watson, 1985; Corydendrium 

corrugatum Nutting, 1905; Cladocoryne haddoni Kirkpatrick, 1890; Solanderia secunda 

(Inaba, 1892); Campanulina panicula G. O. Sars, 1874; Acryptolaria rectangularis (Jarvis, 1922); 

Acryptolaria angulata (Bale, 1914); Lafoea dumosa (Fleming, 1820); Zygophylax rufa (Bale, 1884); 

Salacia punctagonangia Hargitt, 1924; Synthecium flabellum Hargitt, 1924; Antennella campanulaformis 

(Mulder & Trebilcock, 1909). A lectotype is designated for Synthecium samauense Billard, 

1925. Halecium simplex Pictet, 1893 is transferred to Mitrocomium, as M. simplex, n. comb. 

Thecocarpus perarmatus Billard, 1908 is transferred to Lytocarpia, as L. perarmata, n. comb., and T. 

myriophyllum var. orientalis, Billard, 1908 is raised to full species level, as Lytocarpia orientalis, n. 

comb., n. status. Aglaophenia pluma var. sibogae Billard, 1913 is raised to full species level as A. 

sibogae, n. status. 

Keywords: marine Cnidaria, Hydrozoa, Anthoathecata, Leptothecata, taxonomy, revision, new 

species, new records, Kei Islands, Moluccas, Indonesia 

Peter Schuchert, Muséum d’Histoire Naturelle, 1 Route de Malagnou, CH-1211 Geneva, Switzerland. 

E-mail: Peter.Schuchert@MHN.ville-ge.ch 

In 1921, the eminent Danish echinoderm taxonomist 

Theodor Mortensen set out on an expedition 

to the islands of Indonesia, in particular the Kei 

Islands southeast of the Moluccas. The aim of the 

expedition was to evaluate the feasibility of establishing 

a tropical marine biological station. 

For this goal, numerous dredgings were made 

around the Kei Islands, the Banda Islands, the 

Moluccas, and in the Sunda Strait. The account 

of this expedition and most station data were 

published by Mortensen in 1923. Mortensen’s 

collection also included numerous hydroids in 

comparatively good condition. This interesting 

hydroid collection is now kept by the Zoological 

Museum in Copenhagen and, astonishingly, it 

has never been worked up and the species remained 

unidentified. Only Petersen (1990) described 

the new species Ralpharia neira and 

recorded Ectopleura pacifica (Thornely, 1900) 

based on this collection. The present author 

therefore gladly accepted an offer to study this 

collection, moreover as it offered an opportunity 

to concomitantly revise a collection of hydroids 

from the Moluccas collected and described by 

Pictet (1893), a collection now kept by the Natural 

History Museum of Geneva.

138 

The larger thecate hydroid species of Indonesia 

are relatively well known, mostly through the 

studies of Billard (see below). The medusae of 

the region are also quite well known, except 

perhaps the smaller forms (Kramp 1968). In contrast, 

the athecate hydroids and smaller thecate 

hydroids producing medusae are very poorly 

known. These forms can often not be identified in 

dredged material because they require live observation 

and knowledge of the complete life-cycle. 

The first study dealing exclusively with Indonesian 

hydroids was by Pictet (1893). It was based 

on material collected by M. Bedot and C. Pictet 

during an expedition to the Moluccas (Bedot 

1893–1909). Shortly afterwards, this publication 

was followed by the studies of von 

Campenhausen (1896) and Weltner (1900). The 

Dutch Siboga expedition in 1899–1900 produced 

a particularly rich collection of hydroids 

studied thoroughly by Billard (1911a through 

1942b). The investigation on the Stylasteridae of 

the Siboga expedition was published by Hickson 

& England (1906). Also Stechow & Müller 

(1923), Leloup (1930), Vervoort (1941), Cairns 

(1983), and Vervoort (1993) contributed important 

accounts on Indonesian hydroids (see Appendix 

2). For the hydromedusae, the synopsis of 

Kramp (1965, 1968) remains certainly the most 

relevant publication. A newer account is provided 

by van der Spoel & Bleeker (1988). Because 

the hydrozoan fauna of the tropical Indo- 

Pacific is rather homogeneous and certainly belongs 

to one biogeographic unit, systematic studies 

from waters belonging to other economic 

zones often contain essential information. The 

most important of these studies are: Allman 

(1883, 1888), Bale (1884), Thornely (1900, 

1904), Nutting (1905, 1927), Jarvis (1922), 

Millard & Bouillon (1973), Vervoort & Vasseur 

(1977), Bouillon (1978a, 1978b, 1980, 1984b, 

1985b), Gravier-Bonnet (1979), Watson (1985, 

1997, 1999, 2000), Rees & Vervoort (1987), 

Gibbons & Ryland (1989), and Ryland & Gibbons 

(1991). 

The present account deals with hydrozoan 

polyps collected by Mortensen’s Kei Island Expedition 

as well as the hydroid material described 

by Pictet (1893). The numerous new records 

demonstrate that our knowledge of this region is 

still far from being complete. 

P. SCHUCHERT 

MATERIALS AND METHODS 

Materials 

The hydroids of the Danish expedition to the Kei 

Islands are kept by the Zoological Museum, University 

of Copenhagen. Some slide material of 

this collection as well as some alcohol material of 

species collected in great abundance are also in 

the Natural History Museum of Geneva. The 

localities are given – if available – as Kei Islands 

Expedition station numbers. The geographic coordinates 

and further data of these stations are 

given in Appendix 1 and in Mortensen (1923). 

Some material of the Kei Islands Expedition was 

taken at sites without a station number and therefore 

the information on the labels is given here. 

The specimens were examined with a dissecting 

microscope or a compound microscope using 

temporary or permanent preparations on microscope 

slides (see Gibbons & Ryland 1989). 

Drawings based on material examined for this 

study were usually made with the help of a camera 

lucida. The figures given in this publication 

thus enable calculation of linear dimensions. In 

cases where a species was recorded from one 

station only, no locality data are specified in the 

legends of the illustrations. 

Taxonomy and technical terms 

Supraspecific taxa are here used as defined in 

Cornelius (1995a, 1995b), Bouillon (1985a), or 

Millard (1975), except for the Hydractiniidae and 

Cordylophoridae, which are delimited as discussed 

in Schuchert (2001). Additionally, the 

families Tubidendridae Nutting, 1905 and Hebellidae 

Fraser, 1912 are here regarded as valid. 

Technical terms are generally used as explained 

in Cornelius (1995a, 1995b), Millard 

(1975), and Schuchert (1996, 1997). 

Abbreviations 

MHNG Muséum d’Histoire Naturelle, Geneva, 

Switzerland 

NMNH National Museum of Natural History, 

Smithsonian Institution, Washington 

D.C., USA 

ZMUC Zoological Museum of the University 

of Copenhagen, Denmark


Fig. 1. Hydractinia granulata Hirohito, 1988. A. Gastrozooid. 

B. Gonozooid with medusoids. C. Dactylozooid. D. 

Spines and prickles. E. View of distal end of medusoid with 

its rudimentary tentacles and the four radial canals (rc). – 

Scales: A–C, D = 0.2 mm; E = 50 µm. 

ZMA Zoological Museum Amsterdam, The 

Netherlands 

SYSTEMATIC PART 

Order Anthoathecata 

Family Hydractiniidae 

Hydractinia granulata Hirohito, 1988 

Fig. 1. 

Hydractinia granulata Hirohito, 1988: 121, fig. 44. 

Material examined: 

Kei Islands Expedition station 96, 4 gastropod shells (Nassarius 

sp., 2 cm) inhabited by hermit crab Diogenes custos 

(Fabricius, 1798) (kindly identified by Dr Jacques Forest, 

Paris), shells covered completely by hydroid, fertile males. 

139 

Description 

Colonies encrusting and covering nearly whole 

shell, hydrorhiza covered by naked coenosarc, 

provided with densely set spines and numerous 

small prickles. Spines simple, up to 2 mm high, 

smaller ones almost smooth and conical, larger 

ones with longitudinal ridges set with irregular 

prickles. Hydranths polymorphic. 

Gastrozooids 1 mm high (contracted), hypostome 

conical, without belt of nematocysts, 6–14 

tentacles in one whorl. 

Gonozooids smaller and more slender than 

gastrozooids, shaped like ninepins, 6–8 tentacles, 

these shorter than in gastrozooids, hypostome 

with a few larger nematocysts. Gonophores in 

one whorl in middle of hydranth, 4–6 gonophores 

per hydranth. Gonophores are medusoids 

with reduced tentacles, only males observed. 

Dactylozooids present along outer lip of shell 

opening, 1–2 mm, curved, tapering, distal end 

rounded and densely studded with nematocysts. 

Medusoids spherical, diameter about 0.25 

mm, with four thin radial canals and a ring canal 

around the narrow bell-opening, opening surrounded 

by 8 short tentacle stumps. Male gonads 

in four interradial, wedge-shaped packets filling 

the subumbrella completely and hiding the 

manubrium. Nematocysts: a) microbasic euryteles, 

7 x 3 µm, on tentacles; b) heteronemes, (10– 

12) x (3–4) µm, on hypostome of gonozooids and 

abundantly on tips of dactylozooids; c) desmonemes, 

(5–6) x (3) µm, on tentacles. 

Remarks 

This is the second record of this species and the 

first record outside Japan. It is apparently also the 

first record of a Hydractinia species for Indonesia. 

The Indonesian material agrees well with 

Hirohito’s (1988) description. 

Distribution 

Japan, Indonesia. Type locality: Hayama, Sagami 

Bay, Japan. 

Family Tubidendridae 

Diagnosis (emended) 

Anthoathecata Filifera with erect, branched,

140 

polysiphonic colonies. Hydranths polymorphic. 

Gastrozooids with club-shaped body and with 

two well separated whorls of tentacles. Gonozooids 

with either one tentacle or none, with one 

whorl of gonophores. Dactylozooids small, tentacle-like. 

Gonophores released as immature medusae. 

Young medusa with four filiform tentacles, 

manubrium simple. 

Remarks 

When Nutting (1905) described Balea mirabilis, 

he also created the new family Tubidendridae to 

accommodate it. Because the name Balea is preoccupied 

for a gastropod, Stechow (1919: 154) 

renamed the genus Balella. Some authors, e.g., 

Fraser (1938), recognized the family Tubidendridae, 

while Stechow (1922) referred Balella 

to the new subfamily Balellinae of Clavidae 

McCrady, 1859. Millard (1975), Bouillon 

(1985a), and Hirohito (1988) referred the genus 

to the family Bougainvilliidae. Because the 

gonophores of Balella are produced on the body 

of hydranths they can be placed neither in the 

Bougainvilliidae nor the Cordylophoridae (sensu 

Schuchert 2001, the taxon Clavidae is a synonym 

of Hydractiniidae). Because of this and its unique 

tentacle arrangement it is here placed again in the 

family Tubidendridae. The polymorphic, almost 

sessile polyps as well as the young medusae 

suggest close affinities with the Hydractiniidae. 

Nutting (1905) made cross-sections of the stem 

and observed naked coenosarc at the surface. 

This prompted him likewise to associate the 

Tubidendridae with the Hydractiniidae. The 

presence of such naked coenosarc could not be 

seen with sufficient accuracy in the present samples 

and no cross-sections could be made. Further 

discussions on the affinities of Balella 

mirabilis must await information on the adult 

medusa. 

Balella mirabilis (Nutting, 1905) 

Fig. 2. 

Balea mirabilis Nutting, 1905: 940, pl. 2: fig. 3, pl. 7: figs 3– 

4. – Jäderholm 1919: 4, pl. 1: figs 1–4. 

Balella mirabilis. – Hirohito 1988: 91, fig. 32a–c. 


Kei Islands Expedition station 81, about 25 colonies, some 

with medusae buds. 

P. SCHUCHERT 

Description 

Erect hydroid colonies reaching 6 cm in height, 

irregularly pinnate, side-branches primarily in 

one plane. Stem and branches polysiphonic to the 

tips, component tubes neatly parallel and compactly 

fused together. Hydrorhiza a large, tangled 

mass of very fine stolons anchoring the 

colony in the sediment. Polyps polymorphic, 

with gastrozooids, gonozooids, and dactylozooids. 

Gastrozooids up to 1.2 mm high, sitting preferentially 

on upper and under side of the sidebranches 

in a wide and shallow perisarc collar; 

body of gastrozooids with a slender, pedicel-like 

lower part and a swollen, pear-shaped main 

body; nipple-shaped hypostome very high, two 

well separated whorls of filiform tentacles, about 

ten tentacles per whorl, lower whorl of tentacles 

at base of swelling, second whorl at base of 

hypostome, tentacles tapering, evenly covered 

with nematocysts, gastrodermal cells chordoid. 

In younger gastrozooids the two tentacle whorls 

more approximated. 

Gonozooids only half the size or less of 

gastrozooids, very slender and only slightly 

swollen distally, base in a short, tubular perisarc 

collar; at distal end a single, thin tentacle, may be 

absent; at one third from upper end a single whorl 

with 4–6 medusae buds. 

Dactylozooids very numerous and often regularly 

spaced, finger-like, with no or very low 

perisarc collar, epidermis of dactylozooids with 

only few euryteles. 

Medusa buds up to 0.25 mm, oldest observed 

stage with four radial canals, four marginal bulbs, 

each with thick epidermis and a short tentacle, 

manubrium simple, without visible gonad tissue. 

Nematocysts similar to the ones described below. 

Nematocysts: desmonemes, four coils when 

discharged, approx. 4 x 2.5 µm; microbasic 

euryteles, about 7 x 2.5 µm, almond-shaped, 

discharged shaft about as long as capsule, only 

slightly swollen. 

Remarks 

The present material is the first find of this species 

in Indonesian waters. The gonozooids and 

gonophores are here described for the second 

time only. They were first seen by Jäderholm


Fig. 2. Balella mirabilis (Nutting, 1905). A. Silhouette of colony, note massive hydrorhiza. B. Part of branch with 

gastrozooids, gonozooids, and dactylozooids. C. Dactylozooid. D. Gonozooid with medusae buds and tentacle; left of the 

gonozooid an empty perisarc collar of a young gastrozooid. E. Marginal bulb with tentacle of medusa, seen from inside. – 

Scales: A = 1 cm; B = 0.5 mm; C, E = 0.1 mm; D = 0.2 mm 

(1919) in material from Japan and he described 

the gastrozooids as devoid of tentacles. Contrary 

to the material of Jäderholm, the gonozooids of 

the present material usually had a single tentacle 

(Fig. 2D); some, however, were devoid of such a 

tentacle (Fig. 2B). Whether this is due to mechanical 

damage or represents a natural polymorphism 

could not be determined. 

Distribution 

Rare species, occurring at the coasts of Japan, 

Hawaii, and Indonesia; depth range 49–232 m, 

on sandy or muddy bottoms. Type locality: Hawaiian 

Archipelago, between Molokai and Maui, 

232 m. 

Family Stylasteridae 

Conopora major Hickson & England, 1905 

Fig. 3. 

141 

Conopora major Hickson & England, 1905: 25, pl. 3: figs 

33–35. – ?Broch 1936: 91, fig. 30, pl. 13: fig. 38. – 

Boschma 1956: F100, fig. 82, 2c. – Boschma 1957: 39, 

bibliography. – Cairns 1991: 73. 


Kei Islands Expedition station 45, 14 colonies, some 

attached on stones, preserved dry, associated polynoid 

polychaetes often present. 

Description 

Colonies forming erect, calcareous skeleton, 1–4 

cm high, robust, arborescent, not uniplanar, 

branches short, with up to 3 cyclosystems, main 

stem with associated polynoid polychaetes that 

induce trunk to grow into hollow tube with slitlike 

openings. Coenosteum white, microscopic 

texture linear-imbricate, macroscopic texture 

smooth. Nematopores only present locally, preferentially 

near base, rare or mostly absent in 

distal parts of colony, nematopores on shallow 

mounds. Clyclosystems in region inhabited

142 

Fig. 3. Conopora major Hickson & England, 1905. A. 

Colony, height 2.5 cm. B. Schematic organization of the 

cyclosystem, split longitudinally, with ampulla on its side. 

Note that lower dactylopores are not always as distinct as 

shown here. – Scale: B = 0.2 mm. 

by polychaete irregularly arranged, in distal 

branches sympodial in arrangements, shifted 

only slightly to one side of branch, distal ones 

slightly standing out, proximal ones flush to 

slightly recessed into branch coenosteum. Cyclosystems 

circular to slightly irregular in shape, 

1 mm in diameter, 9–16 dactylopores per nondiastemate 

cyclosystem (mean 12.2, S.D. 1.6, n = 

P. SCHUCHERT 

47, 10 colonies, most frequent value (mode) 12), 

one pseudoseptum occasionally thicker than others, 

adaxial dactylopores of older cyclosystems 

often filled by coenosteum (diastema). Gastropores, 

about 0.4 mm in diameter. Gastropore 

tubes up to 1.2 mm deep, divided into three 

sections of approximately same height. Upper 

section cylindrical, bordered by pseudoseptae; 

below this part a middle section delimited below 

by the ring of the lower dactylopores; lowest part 

hemispherical, not delimited by constriction 

from middle part or constriction very shallow and 

indistinct. Ring of lower dactylopores can be 

absent. Ampullae internal, ellipsoidal cavities, 

only present around cyclosystems; efferent pores 

on the pseudoseptae or in the gaps between them. 

Remarks 

The present samples came from a site near the 

Kei Islands that is only about 40 km away from 

one of the type localities of Conopora major. All 

colonies showed little variation and matched perfectly 

the description of Conopora major given 

in Hickson & England (1905), notably also the 

colony form (Fig. 2A). Broch (1936) assigned 

material from Mauritius to C. major. His colonies 

were more or less regularly pinnate and had their 

cyclosystems on the anterior side only. Furthermore, 

the diameter of the cyclosystems in 

Broch’s samples measured 1.5–1.8 mm in diameter, 

which is considerably more than the 1 mm 

observed here, or the 1.2 mm observed by 

Hickson & England (1905). Thus, the population 

studied by Broch perhaps belongs to another 

species, but due to the lack of information on the 

geographic variability of this species it seems 

impossible to draw reliable conclusions. 

Cairns (1991) re-described the closely similar 

Conopora verrucosa (Studer, 1878) and regarded 

Conopora major as a potential junior 

synonym. Cairns’ (1991) material from New 

Zealand differs from the present one by having a 

uniplanar growth versus a bushy and irregular 

growth; by the abundant nematopores that make 

the surface warty while in the present material 

these nematopores are quite rare; by the longer 

branches with more than 3 cyclosystems; by 

gastropores that are twice as deep, and by the 

regular presence of a constriction in the gas-


tropore. These differences, and in particular the 

difference in colony form, made me hesitate to 

synonymize C. verrucosa and C. major. 

Distribution 

Indonesia, ?Mauritius. Type localities: Kei Islands 

(5°28.4’S, 132°00.2’E, 204 m) and Sulawesi 

(1°33.5’N, 124°41’E, 1901 m). 

Family Cordylophoridae 

Turritopsis cf. nutricula McCrady, 1859 

Fig. 4. 

Turritopsis nutricula McCrady, 1959: 55, pls 4–5. – Russell 

1953: 115, figs 54A–C, 55, 56, pl. 5: figs 1–5, pl. 29. – 

Kramp 1968: 27, fig. 66. – Millard 1975: 76, figs 24F–G. 

– Calder 1988: 8, figs 5–6, synonymy. – Schuchert 1996: 

16, fig. 5a–e, synonymy. – Migotto 1996: 11, fig. 3a–c. 

Fig. 4. Turritopsis nutricula McCrady, 1859; material from 

Ambon. A. Shoot with medusae buds. B. Advanced medusa 

bud, note the coloured interradial patches (stippled). – 

Scales: A = 0.5 mm; B = 0.1 mm. 

143 

?Dendroclava Dohrnii Weismann, 1883: 26. – Pictet 1893: 

6, pl. 1: figs 1–2. 

?Corydendrium chevalense Thorneley, 1904: 109, pl. 1: fig. 

4. 


Kei Islands Expedition, 28.02.1922, Ambon, harbour pier, 1 

m, on Pennaria disticha and sponges, with medusae buds. – 

Kei Islands Expedition station 37, on hydroids and other 

material, with medusae buds. – MHNG INVE 31269, Bay of 

Ambon, material of Pictet (1893), labelled Dendroclava 

Dohrni, collected 15.7–12.8.1890, on Pennaria disticha, 

with medusae buds, preserved with HgCl 2 . – MHNG INVE 

32617, Thailand, Andaman Sea, Koh Bi Da Nok, coll. A, 

Faucci, 6 Apr 2000, 12–18 m, with medusae buds. – MHNG 

INVE 29753, Mediterranean, Mallorca, Cala Murada, 

16.8.2000, 2 m, examined alive, newly released medusae 

observed. – New Zealand material: see Schuchert (1996). 

Description 

Hydroid branched, monosiphonic or polysiphonic, 

0.5–2 cm in height, arising from creeping, 

reticulate stolons. Branches and pedicels of hydranths 

adnate for some distance then curving 

outwards, diameter of branches 0.1–0.15 mm. 

Perisarc double layered, outer layer straight, 

inner layer undulated. Hydranths 0.5–1.0 mm, 

spindle-shaped, with up to 20 filiform tentacles 

scattered in distal ¾ of hydranth. Gonophores 

medusae developing on hydranth pedicels (in 

perisarc-covered region). Medusa buds spherical. 

Oldest buds observed with 4 radial canals, 

several tentacles, 8 eye-spots, manubrium with 

four interradial pads consisting of large, darkly 

coloured cells. Nematocysts: desmonemes 3.5 x 

2 µm, microbasic euryteles (5.5–6) x (2.5–3) µm. 

Remarks 

Turritopsis hydroids and young medusae possess 

some characteristic traits that facilitate their identification: 

the double-layered perisarc and the 

interradial patches of coloured cells on the manubrium 

of the medusa. The first Indonesian record 

of a hydroid referable to Turritopsis was made 

by Pictet (1893, as Dendroclava dohrni). Reexamination 

of Pictet’s original material clearly 

showed that it belongs to Turritopsis. The medusa 

phase of Turritopsis is also known to occur 

in the region (Kramp 1968, as T. nutricula). 

Although the hydroid phase and young medusa 

of the specimens from Indonesia, the Andaman 

Sea, New Zealand, and the Mediterranean appear

144 

identical and they agree with the current concept 

of T. nutricula (see Schuchert 1996), there still 

remains the possibility of sibling hydroid species 

producing different adult medusae. According 

to Kramp (1961, 1968), there are only two valid 

Turritopsis medusae, T. nutricula and T. lata 

von Lendenfeld, 1885. Results from ongoing 

research (P. Schuchert, publication in prep.), 

however, suggest that Turritopsis medusae from 

various populations differ significantly and that 

T. nutricula as presently conceived is very likely 

a species complex. The Indonesian material was 

therefore only tentatively assigned to T. nutricula, 

pending further information on the medusa 

phase of this population. The Turritopsis species 

of the tropical Indo-Pacific might all be referrable 

to Turritopsis chevalense (Thorneley, 1904), 

a hydroid known from Ceylon. Turritopsis chevalense 

is only known from its polyp phase and at 

present not distinguishable from other Turritopsis 

hydroids. 

Distribution 

Circumglobal, mainly in tropical waters but 

spreading into temperate waters too. Type locality: 

Charleston Harbour, South Carolina, USA. 

Corydendrium cf. corrugatum Nutting, 1905 

Fig. 5. 

Corydendrium corrugatum Nutting, 1905: 941, pl. 2: fig. 2, 

pl. 7: figs 5–7. 


Kei Islands Expedition stations 74. – 107. – For comparison: 

MHNG INVE 25127, Corydendrium parasiticum, Mediterranean, 

Naples, fertile males. 

Description 

Colonies up to 4 cm high, arising from tangled, 

tortuous stolons. Colonies polysiphonic, stout, 

branching irregularly, diameter of terminal 

branches (hydranth pedicels) about 0.4 mm. 

Perisarc thick, not regularly two-layered, slightly 

and irregularly corrugated or folded, ending 

abruptly below base of hydranths. Branches 

adnate for most of their length, then curving 

outwards, preferentially on one side of branch, 

free part about 1 mm. Contracted hydranths 1.5 

mm long, with about 20 scattered filiform tentacles. 

Sporosacs not seen. 

P. SCHUCHERT 

Fig. 5. Corydendrium cf. corrugatum Nutting, 1905; station 

107. Lateral view of part of stem, without hydranths. – Scale: 

0.5 mm. 

Remarks 

Nutting’s (1905) Hawaiian material as well as the 

present material was infertile, thus the genus 

allocation must remain preliminary only. In view 

of this lack of knowledge of the gonosome, and 

also the relatively simple structure of this hydroid 

offering few reliable distinguishing characters, 

the identification must considered to be only 

tentative. 

The structure of the trophosome of the Indonesian 

specimens matched rather well the description 

and figures given by Nutting (1905) for C. 

corrugatum, except for the annulation of the 

terminal part of the cauli. These free, terminal 

parts were longer and had only irregular corrugations 

and not the broad, regular annulation depicted 

by Nutting (1905). Because perisarc annulation 

in hydroids is often highly dependent on 

environmental conditions, not too much weight 

should be placed on this difference. 

Compared to Mediterranean material of Corydendrium 

parasiticum (Linnaeus, 1767), a species 

forming similar colonies as C. corrugatum, 

the Indonesian Corydendrium is much more robust 

(thicker), the free terminal branches (hy-


dranth pedicels) are shorter and they are preferentially 

on one side only, thus creating branches 

with an anterior and rear side, a trait typical for C. 

corrugatum. In C. parasiticum, the hydranths are 

primarily held sideways. 

Distribution 

Hawaii, ?Indonesia. Type localities: South of 

Oahu, 582 m, and northeast coast of Maui, 181 m 

(Nutting 1905). 

Family Bougainvilliidae 

Garveia clevelandensis Pennycuik, 1959 

Fig. 6. 

Garveia clevelandensis Pennycuik, 1959: 166, pl. 2: figs 7– 

9. 


MHNG INVE 31975, harbour of Ambon, collected 1890 by 

M. Bedot and C. Pictet (see Pictet 1893), on hydroid labelled 

as S. vegae (correct id. is Dynamena crisioides, see below). 

Fig. 6. Garveia clevelandensis Pennycuik, 1959. A. Single 

shoot of a colony. B. Terminal portion with hydranth and 

sporosac. C. Sporosac with egg. – Scales: A = 0.5 mm; B = 

0.2 mm; C = 0.1 mm. 

145 

Description 

Colonies growing on Dynamena crisioides, 

erect, branched up to second order, height reaching 

4 mm. Stolons creeping, ramified. Stems 

evenly thick, monosiphonic, about 0.15 mm diameter, 

densely covered by fine silt particles, 

periderm ends below tentacles of hydranths as 

pseudohydrotheca, pseudohydrotheca not much 

dilated and not sheathing base of tentacles. Periderm 

thin, without regular annulations. Hydranth 

0.25 mm long, with 8–14 tentacles (10 or 12 most 

frequently), tentacles in one whorl; hypostome 

prominent, conical. Gonophores arise on stem 

and branches, pear-shaped, up to 0.2 mm. Gonophores 

are sessile sporosacs without any radialor 

circular canals, spadix simple, females bearing 

a single egg, gonophore covered by thin periderm 

lamella. Development takes place within 

sporosac. Male gonophores unknown. 

Remarks 

The present material corresponds very well with 

the description and figures of Pennycuik (1959), 

only the diameter of the stem being greater 

in the present material. This is the second find 

of this species and also a new record for Indonesia. 

Garveia clevelandensis closely resembles 

Garveia franciscana (Torrey, 1902) in its finer 

structure, especially the monosiphonic colony 

and the sporosacs with one egg only (see 

Vervoort 1964 or Morri 1982 for a description of 

G. franciscana). Garveia franciscana differs 

only in forming much larger colonies (7–20 cm) 

and in preferring brackish waters. The dense 

covering with silt particles found in Garveia 

clevelandensis could be another difference of 

diagnostic value. Garveia nutans Wright, 1859 

forms up to 2.5 cm high colonies that are usually 

polysiphonic, but fertile, monosiphonic colonies 

are possible (MHNG INVE 31852). Monosiphonic 

Garveia nutans can be distinguished from 

G. clevelandensis by their higher number of eggs 

per sporosac (6–10). 

Distribution 

Queensland, Moluccas (new record). Type locality: 

Cleveland, Queensland, Australia; on Dynamena 

crisioides growing on jetty piles.

146 

Family Eudendriidae 

Eudendrium kirkpatricki Watson, 1985 

Eudendrium generale. – Kirkpatrick 1890: 607, pl. 15: figs 

1–2. 

Eudendrium capillare. – Stechow 1925: 202. 

Eudendrium kirkpatricki Watson, 1985: 194, figs 35-39. – 

Watson 1999: 5, fig. 4A–D. – Marques et al. 2000: 98, 

figs 58–63. 


Kei Islands Expedition station 106, infertile. – Kei Islands 

Expedition, Sulawesi, Ujungpandang, Samalon Island, 25 

m, 29 Jun 1922, fertile female, 5-cm shoots, on Nemertesia 

indivisa. – Kei Islands Expedition, Moluccas, Bay of Ambon, 

128 m, 25 Feb 1922, fertile female, 2-cm shoots, on 

organic polychaete tube. 

Description 

Colonies erect, 2–5 cm high, branched, monosiphonic, 

often one longer main stem with shorter 

side-branches, stolons creeping. Stem diameter 

around 0.2 mm, hydranth-cauli diameter around 

0.12 mm. Hydranths relatively small (0.4 mm), 

18–20 tentacles in one whorl, hypostome globular. 

Female sporosacs develop on nearly fully 

formed hydranth, one whorl of 3–8 sporosacs, 

spadix simple. During later development spadix 

reduced and the tentacles of the hydranth shortened 

to stumps. Eggs are ultimately attached by 

means of a membrane to the perisarc-covered 

pedicels of blastostyles. Nematocysts: microbasic 

euryteles abundant on tentacles, (7–8) x 

(2.5–3.5) µm; microbasic eurytele, few (< 8) 

capsules on hydranth body, oblong oval, shaft 

thick in undischarged and discharged capsule, 

shaft shorter than capsule, discharged directed 

sideways, size (22–25) x (11–13) µm in first two 

samples, (31–35) x (13.5–15) µm in third sample. 

Remarks 

Eudendrium kirkpatricki is here for the first time 

recorded for Indonesia. The Indonesian material 

agrees well with the description given by Watson 

(1985, 1999) except for the size of the larger 

microbasic euryteles, which were smaller in two 

samples. Unfortunately, no male colonies were 

seen. It is desirable to have information on the 

male blastostyles in order to assure a full congruence 

of the Indonesian population with the Australian 

one. The previous records along northern 

P. SCHUCHERT 

Australia, however, are rather close to the present 

ones, which fall within the known range of this 

species. 

There were other Eudendrium colonies in the 

present collection which resembled the ones described 

here, but had different nematocysts, either 

isorhizas or egg-shaped microbasic euryteles. 

Due the lack of gonophores, they were not 

assigned to a species. 

Distribution 

Tropical Australia, Red Sea, Indonesia. Type 

locality: Torres Strait, 09°55’S, 144°08’W. 

Family Cladocorynidae 

Cladocoryne haddoni Kirkpatrick, 1890 

Fig. 7. 

Cladocoryne haddoni Kirkpatrick, 1890: 605, pl. 14: fig. 2. 

– Jäderholm 1903: 263. – Ritchie 1910b: 805. – Bouillon, 

Boero & Seghers 1987: 281, figs 2–4. 

Material examined : 

Kei Islands Expedition, Ambon, harbour pier, 1 m, 28 Feb 

Fig 7. Cladocoryne haddoni Kirkpatrick, 1890. – Scale: 0.5 

mm.


1922, on Pennaria disticha and sponges, infertile. – Kei 

Islands Expedition, Banda Islands, Lonthoir Channel, 25 m, 

11 Jun 1922, on bivalve, infertile. 

Description 

Colonies stolonal or rarely branched once, reaching 

heights of about 4–8 mm. Perisarc mostly 

smooth, thin, ending abruptly below hydranth. 

Hydranths spindle-shaped, with two aboral 

whorls of branched tentacles and one whorl of 

short capitate tentacles around mouth. Aboral 

tentacles longer than hydranth height, tapering, 

about 8 per whorl, the two whorls clearly separated, 

each tentacle with two lateral rows of short 

capitate side-branchlets, sometimes also a row of 

such branchlets on upper side of tentacle. Oral 

tentacles 6–8, short, adnate, with terminal capitae. 

On hydranth body, halfway between oral 

and aboral tentacles, five or more oblong pads 

with large macrobasic euryteles. Gonophores 

absent. 

Additional data 

According to Bouillon, Boero & Seghers (1987), 

the gonophores develop into elongated medusoids 

with radial canals, marginal bulbs, but 

without tentacles. Females with 10–20 big, yellowish 

eggs. Embryos develop in situ. 

Remarks 

Following Philbert (1936), many subsequent authors 

regarded Cladocoryne haddoni as a synonym 

of C. floccosa. Bouillon, Boero & Seghers 

(1987) re-described C. haddoni based on material 

from Papua New Guinea and found sufficient 

differences to C. floccosa to permit a reliable 

identification, even of immature specimens. 

Cladocoryne haddoni differs from C. floccosa 

by having only two instead of three whorls of 

branched tentacles, by having nematocyst pads in 

one ring on the hydranth body in the region 

between the oral and branched tentacles rather 

than at the bases of the oral and the branched 

tentacles, and finally by developing oblong gonophores 

distal to the branched tentacles and not 

more spherical ones among the tentacles. 

The present material of C. haddoni – although 

infertile – agrees well with the account of Bouillon, 

Boero & Seghers (1987). 

147 

Cladocoryne haddoni is here recorded for the 

first time for waters belonging politically to Indonesia; 

however, from a biogeographic point of 

view this species is already known from the 

region as the type locality in the Torres Strait is 

very close to the present findings and also the 

records from Papua New Guinea belong to this 

geographic region. 

Other Indonesian findings of Cladocoryne 

species were reported by Stechow & Müller 

(1923) and Vervoort (1941). Stechow & Müller 

(1923) identified their material as Cladocoryne 

pelagica Allman, 1876. Allman’s (1876) description 

of Cladocoryne pelagica found on Atlantic 

Sargassum is not precise enough to allow a 

reliable separation from C. floccosa. Allman’s 

figure shows a hydranth which apparently has 

only one whorl of branched tentacles, but reexamination 

of the type material must confirm 

whether this is correct. It was not possible to 

locate this type material. The material of Stechow 

& Müller (1923) originating from the Aru Islands 

was re-examined for this study (the specimens 

are kept by the “Zoologische Staatssammlung”, 

Munich, Germany). It is a well preserved, typical 

Cladocoryne species growing on the hydroid 

Idiellana pristis. The hydranths have one or two 

very closely set whorls of aboral tentacles. If two 

whorls are present, they are closer together as in 

the material from the Kei Islands. One hydranth 

had a small, spherical gonophore which developed 

distal to the aboral tentacles. Despite careful 

examination, I was unable to see any nematocyst 

pad on the hydranth body, although discharged 

macrobasic euryteles could regularly be found 

in the cauli and on the hydranths. I suspect 

that this hydroid is not C. haddoni and that there 

exist more Cladocoryne species than previously 

thought. Vervoort’s (1941) material identified by 

him as C. floccosa had 3–4 whorls of branched 

tentacles, each with four tentacles only. Normally 

both C. floccosa and C. haddoni have 

about eight tentacles per whorl and Vervoort’s 

Cladocoryne could therefore be another, so far 

unnamed species. 

Distribution 

Torres Strait, Papua New Guinea, Moluccas, 

Banda Islands, Mergui Islands, coast of India.

148 

Type locality: Murray Island, Torres Strait, Australia, 

27–37 m. 

Pteroclava crassa (Pictet, 1893) 

Syncoryne crassa Pictet, 1893: 8, pl. 1: figs 3–4. – Boero, 

Bouillon & Gravier-Bonnet 1995: 71. 

Remarks 

No new material of this species could be obtained. 

Examination of the type material of 

Syncoryne crassa Pictet, 1893 (MHNG INVE 

25777) showed that it has moniliform tentacles 

and thus conforms to the genus Pteroclava (see 

Boero, Bouillon & Gravier-Bonnet 1995). Additionally, 

the few gonophores present revealed 

that they must develop into medusae with only 

two tentacle bulbs. The material strongly resembles 

Pteroclava krempfi (Billard, 1919a). However, 

Pteroclava krempfi is only known to occur 

on Octocorallia while Pteroclava crassa was 

found on the hydrorhiza of the hydroid Macrorhynchia 

philippina. Boero, Bouillon & Gravier- 

Bonnet (1995) regarded them therefore as separate 

species. 

Family Pennariidae 

Pennaria disticha Goldfuss, 1820 

Pennaria disticha Goldfuss, 1820: 89. – Brinckmann-Voss 

1970: 40, text-figs 43, 45–50. – Gibbons & Ryland 1989: 

387, fig. 5. – Schuchert 1996: 142, fig. 85a–c. – Migotto 

1996: 25. 

Pennaria Cavolinii Ehrenberg, 1834: 297. – Pictet 1893: 12, 

pl. 1: figs 7–9. – von Campenhausen 1896b: 307. – 

Weltner 1900: 585. 

Pennaria australis Bale, 1884: 45. 

Halocordyle disticha var. australis. – Vervoort 1941: 192. 

Halocordyle disticha. – Millard 1975: 41, figs 16C–G. – 

Garcia-Corrales & Aguirre 1985: 85, figs 1–3, synonymy. 

– Calder 1988: 57, figs 43–45, synonymy. – Östman 

et al.1991: 607, figs 1–18. – Hirohito 1988: 28, fig. 9a– 

d, pl. 1: fig. C. 


Kei Islands Expedition stations 11. – 104, fertile. – 116. – 

Kei Islands Expedition, Moluccas, Ambon, pier of harbour, 

1 m, 28.02.1922, well preserved and fertile. – MHNG INVE 

31269, Bay of Ambon, material of Pictet (1893), jar labelled 

Dendroclava Dohrni, collected 15 Jul–12 Aug 1890, with 

mature medusoids. – MHNG INVE 29809, Mediterranean, 

Mallorca, Cala Murada, 1 m, coll. 24 Aug 2000. 

Diagnosis 

Anthoathecata Capitata with hydroid phase 

P. SCHUCHERT 

forming erect, pinnately branched stems, height 

10 cm and more, hydranths on upper side of 

branches, pedicellate, body pear-shaped, one 

aboral whorl of filiform tentacles and distal to 

them scattered capitate tentacles. Gonophores 

oblong medusoids without tentacles, short-lived, 

released with mature gonads. 

Remarks 

This characteristic and well known species needs 

no special comments. Its synonymy is well 

known and there were no significant differences 

between the Pacific and Mediterranean material. 

According to current usage, the genus name 

Pennaria is preferred over Halocordyle (see 

Schuchert 1996). 

Distribution 

Circumglobal in tropical to warm-temperate waters. 

Type locality: Gulf of Naples, Mediterranean. 

Fig. 8. Solanderia secunda (Inaba, 1892). A. Colony silhouette. 

B. Skeleton of terminal branch with triangular 

hydrophores. – Scales: A = 3 cm; B = 0.2 cm.

Family Solanderiidae 


Solanderia secunda (Inaba, 1892) 

Fig. 8. 

Dendrocoryne secunda Inaba, 1892: 98, figs 111–113. 

Solanderia secunda. – Hirohito 1988: 49, fig. 15. – Bouillon, 

Wouters & Boero 1992: 12, pls 5–6, 10–12, synonymy. – 

Watson 1999: 13, fig. 9A–F. 

Solanderia minima. – Millard & Bouillon 1973: 16, fig. 2A– 

B, pl. 1. – Millard 1975: 59, fig. 21C–E. 


Kei Islands Expedition, Banda Islands, Neira Island, 25 m, 

coll. 14 Jun 1922, without gonophores, colony broadly fanshaped, 

dimension 22 x 18 cm, stem and thicker branches 

darkly coloured. 

Diagnosis 

Solanderiidae with hydranth bases flanked by 

two parallel, broadly triangular periderm processes 

(hydrophores). 

Remarks 

This is the first find of S. secunda in Indonesian 

waters, but it lies well within the known distribution 

of this species. All Solanderia species have 

recently been revised by Bouillon, Wouters & 

Boero (1992) and several nominal species were 

synonymized. For detailed descriptions of this 

species see Bouillon, Wouters & Boero (1992), 

Millard (1975, as S. minima), or Watson (1999). 

Distribution 

Tropical and subtropical Pacific and Indian 

Ocean, reaching from Japan over Australia to 

South Africa and the Red Sea. Type locality: 

Misaki, Japan. 

Family Tubulariidae 

Ectopleura viridis (Pictet, 1893) 

Fig. 9. 

Tubularia viridis Pictet, 1893: 17, pl. 1: figs 10–11. – Billard 

1905: 331, figs 1–3. 

Ectopleura pacifica Thornely, 1900: 452, pl. 44: figs 1, 1a. 

New synonym. 

Ectopleura pacifica. – Petersen 1990: 165. – Schuchert 

1996: 112. 

Tubularia pacifica. – Borradaile 1905: 838. 

Not Ectopleura pacifica. – Mammen 1963: 59, figs 27–29 

[= Ectopleura indica Petersen, 1990]. 

149 

Fig. 9. Ectopleura viridis (Pictet, 1893); after type material. 

Hydranth with part of caulus. – Scale: 1 mm. 

Type material examined: 

MHNG INVE 31350, coll. Pictet and Bedot, 14 Aug 1890, 

Port of Ambon, Moluccas, on sponge, depth 1 m, several 

stems with medusa buds. 

Other material examined : 

Kei Islands Expedition, labelled as Ectopleura pacifica, 

Banda Islands, off Neira Island, 10 m, on Melitodes ochracea 

(Octocorallia), 1.06.1922, several stems with medusae 

buds. – ZMUC, as Ectopleura pacifica, Laing Island, Papua 

New Guinea, 40 m, July 1977, coll. J. Bouillon, on crab; 

solitary, very short hydroids, perhaps does not belong to E. 

viridis. 

Description 

Hydroid erect, 0.5–1.0 cm, stems not branched, 

smooth, curved or not, 0.3–0.4 mm diameter, 

periderm firm, transparent, at distal end of caulus 

a neck-region, neck-region with filmy perisarc 

which originates below distal end of stem, with 

collar formation (see Petersen 1990). Hydranth 

body ovoid, 1.0–1.2 mm high, one whorl of 16– 

20 oral tentacles, oral tentacles relatively short 

and stubby, nematocysts concentrated at tip. At 

hydranth base on whorl of 18–25 long, filiform

150 

tentacles, nematocysts more concentrated on underside. 

Gonophores develop in a whorl just above the 

aboral tentacles, up to about 12 blastostyles bearing 

1–6 medusae buds, blastostyles not longer 

than oral tentacles. Oldest, but still attached, 

medusa-stage with two tentacle bulbs and eight 

meridional tracks of nematocysts on exumbrella. 

Radial canals of equal length. Mature medusa 

unknown. 

Further details (fide Pictet 1893): stolons 

creeping, hydranth colour: yellowish-green. 

Remarks 

Re-examination of the type material of Ectopleura 

viridis (Pictet, 1893) permitted extraction 

of some additional details neither mentioned 

in Pictet (1893) nor Billard (1905). Ectopleura 

viridis is a small, but typical tubulariid hydroid. 

The base of the caulus is deeply embedded in the 

sponge tissue. The oral tentacles are not in two 

distinct whorls as stated by Pictet, but only one 

whorl, with an occasional tentacle very slightly 

displaced. The neck region corresponds to the 

one for an Ectopleura species in the sense of 

Petersen (1990). The gonophores are medusae 

with two marginal bulbs and eight meridional 

tracks of exumbrellar nematocysts. The original 

fixation with HgCl apparently stained the nem- 

2 

atocysts brown and thus rendered them visible 

even under the stereo microscope. 

With this additional information, Ectopleura 

viridis becomes indistinguishable from E. pacifica 

Thornely, 1900, except perhaps for the 

slightly thicker stem in the former species and the 

difference of substrates. I am convinced that they 

are conspecific. 

Petersen (1990) also reported Ectopleura pacifica 

from Papua New Guinea, growing on a 

crab. This sample was re-examined and it is 

somewhat uncertain that it belongs to E. pacifica 

or E. viridis because the polyps are solitary and 

the stems only about 1 mm long. It produces also 

a two-tentacled medusa. 

Distribution 

Indonesia, Papua New Guinea, Gambier Islands, 

Maldives. 

P. SCHUCHERT 

Order Leptothecata 

Family Campanulinidae 

Campanulina panicula G. O. Sars, 1874 

Fig. 10. 

Campanulina panicula G. O. Sars, 1874: 121, pl. 5: figs 9– 

13. – Kramp 1941: 1, figs 1–5. – Cornelius 1995a: 190, 

fig. 43. – Schuchert 2001: 56, fig. 41. 

Campanulina denticulata Clarke, 1907: 12, pl. 8. 

Opercularella panicula. – Leloup 1974: 4, fig. 3. – Ramil & 

Vervoort 1992: 25, fig. 3a–d, synonymy. – Hirohito 

1995: 91, fig. 25d–e. 

Campanulina (?)indivisa Fraser, 1948: 216, pl. 24: fig. 7. – 

Vervoort 1966: 106. 

Opercularella denticulata. – Gili, Vervoort & Pagès 1989: 

76, fig. 6a. 


Kei Islands Expedition station 42, large colony overgrowing 

axial skeleton of gorgonid octocoral, infertile. 

Description 

Colonies with erect stems arising from thin, 

creeping stolons. Stems up to 2 cm high, monosiphonic, 

0.15–0.2 mm thick, perisarc smooth. 

Along stem in more or less regular intervals sidebranches 

formed by pedicellate hydrothecae, all 

directed towards one side, often roughly in two 

rows forming an angle smaller than 180°, some 

hydrothecal pedicels branched. Pedicels of hy- 

Fig. 10. Campanulina panicula G. O. Sars, 1874. Part of 

stem in side view with hydrothecae. Scale: 0.2 mm.


drothecae 0.3–0.8 mm long, at base with or without 

annulation. Hydrotheca cylindrical, height 

without operculum about 0.3 mm, perisarc thin 

and filmy, hydrotheca at base with slight constriction 

where hydranth-base is attached and 

forms a diaphragm-like shelf; operculum conical, 

formed by about 10 triangular flaps, these 

not demarcated from hydrotheca by crease line. 

Gonothecae absent. 

Remarks 

The present material of Campanulina panicula 

was indistinguishable from similar Atlantic material 

(Schuchert 2001). This is the first record for 

Indonesia for this species, but this find fits well 

into its circumglobal occurrence. 

Distribution 

Moderately deep to deep waters of the Atlantic, 

Pacific and Indian Oceans, including the Mediterranean 

(Ramil & Vervoort 1992). Type locality: 

Oslo Fjord near Drøbak, Norway, 90–100 m. 

Family Haleciidae 

Hydrodendron sibogae (Billard, 1929) 

Fig. 11. 

Diplocyathus sibogae Billard, 1929a: 70, fig. A. 

Hydrodendron sibogae. – Leloup 1938: 1, fig. 3. – Hirohito 

1995: 38, fig. 11a–c, pl. 3: fig. B. 


Kei Islands Expedition, Moluccas, Bay of Ambon, 90 m, 2 

Mar 1922, on stones and sand. 

Description 

Colonies up to 10 cm high and broad, irregularly 

branched, stem and major branches polysiphonic; 

short and thin monosiphonic branches originating 

from polysiphonic ones. Monosiphonic 

branches geniculate and with more or less distinct 

nodes, nodes alternately oblique, segments 

about 0.4 mm long, with broad and short apophyses 

for the attachment of hydrothecae at proximal 

end of segments, apophyses alternate on lateral 

sides. 

In upper axil of apophysis a tubular nematotheca, 

length about 0.07 mm, with a tentacle-like 

nematophore having a swollen distal end. 

151 

Fig. 11. Hydrodendron sibogae (Billard, 1929). A. Monosiphonic 

part of branch. B. Hydrotheca, hydrophore, and 

nematotheca with nematophore; soft tissue stippled. – 

Scales: A = 0.2 mm; B = 0.1 mm. 

Hydrotheca movable, on a long (0.2 mm), 

conical hydrophore. Hydrotheca about 20–30 

µm deep, diameter 0.1 mm, walls converging, 

straight or slightly everted, ring of refringent 

nodules on inside. 

Gonothecae not present. 

Remarks 

The gonothecae of this species are bell-shaped 

with a broad, truncated end, about 1 mm high and 

0.5–0.7 mm broad, growing on the main stem and 

branches (Hirohito 1995). 

The hydrophores of the present material were 

about 1/3 shorter than those observed by Billard 

(1929a) and Hirohito (1995). 

In its microscopic structure, especially the 

present sample with its somewhat shorter hydrophores, 

Hydrodendron sibogae closely resembles 

Hydrodendron dichotomum (Allman, 1888) 

(see, e.g., Rees & Vervoort 1987, Watson 2000). 

The polysiphonic stem of the former species 

seems to be the only reliable character to separate 

it from H. dichotomum. 

Distribution 

Japan, Indonesia. Type locality: “Indonesia”.

152 

Halecium halecinum var. minor Pictet, 1893 

Halecium halecinum var. minor Pictet, 1893: 20, pl. 1: figs 

14–15. 


MHNG INVE 31408, type colony of H. halecium var. minor, 

coll 10 Aug 1890 by M. Bedot and C. Pictet, Bay of Ambon, 

Indonesia. 

Description 

Colonies 2–4 cm high, branching irregularly, 

primarily in one plane; main stem and some 

side-branches polysiphonic from which arise 

monosiphonic branches. Monosiphonic parts 

with regular nodes, these transverse to slightly 

oblique. Hydrothecae on alternating sides of 

distal ends of internodes, sessile, adcauline wall 

adnate to internode, hydrothecal wall very short, 

straight, opening slightly tilted downwards. Gonothecae 

absent. 

Dimensions 

Length of internodes about 0.5 mm, diameter of 

hydrotheca 0.13 mm, depth of hydrotheca 20 µm. 

Remarks 

Pictet’s colonies lack the typical regular and parallel 

side-branches of H. halecinum (Cornelius 

1995a, Schuchert 2001). Furthermore, H. halecinum 

is a species mostly known from temperate 

to cool waters. It is therefore improbable that the 

present material genetically belongs to H. halecinum. 

The material also conforms with H. sessile 

Norman, 1876, a species which is reportedly 

cosmopolitan (Millard 1975, Hirohito 1995) and 

which has been recorded in Indonesian waters 

by Vervoort (1941). Likewise, Pictet’s material 

could also be identified as H. beanii, a species 

closely resembling H. sessile. However, in the 

absence of information on the gonotheca, Pictet’s 

material cannot be identified with sufficient accuracy. 

Distribution 

Only known with certainty from type locality: 

Bay of Ambon, Indonesia. 

P. SCHUCHERT 

Fig. 12. Halecium humile Pictet, 1893; after type material. A. 

Single shoot. B. Hydrotheca and side-branch. – Scales: A = 

0.5 mm; B = 0.1 mm. 

Halecium humile Pictet, 1893 

Fig. 12. 

Halecium humile Pictet, 1893: 23, pl. 1: figs 16–17. 


MHNG INVE 25036, Port of Ambon, Moluccas, slide and 

alcohol material, 1 mm high shoots with 2–3 hydranths, 20– 

22 tentacles, internode walls smooth. 

Remarks 

No new material of this species could be obtained. 

Its gonothecae are unknown, which 

makes identification difficult. The hydrothecae 

are very shallow and much everted (depth 50 µm, 

diameter at diaphragm 150 µm, at rim 220 µm) 

and might render the species recognizable. It 

closely resembles Halecium pygmeum Fraser, 

1911 (see Fraser 1937, Hirohito 1995). Also 

Halecium sp. 1 depicted in Gibbons & Ryland 

(1989) might belong to it. A similar Indonesian 

species is Halecium scalariformis Billard, 1929c, 

which, however, has straight hydrothecal walls. 

New material from the type locality must be 

examined to complement the description of H. 

humile. 

Distribution 

Only known from type locality: Port of Ambon, 

Moluccas.


Mitrocomium simplex (Pictet, 1893), n. comb. 

Halecium simplex Pictet, 1893: 22, pl. 1: figs 16–17. – 

Ritchie 1910b: 807, pl. 77: figs 10–11. 

Campalecium cirratum. – Millard & Bouillon 1975: 7, fig. 

2C–E. 


MHNG INVE 25037, as Halecium simplex Pictet, 1893, Bay 

of Ambon. 

Remarks 

The taxonomic situation of the various species 

referable to Campalecium or Mitrocomium is 

complicated and unresolved (see Calder 1991). 

The following hydroids referable to the genus 

Campalecium have been described: C. simplex 

(Pictet, 1893); C. medusiferum Torrey, 1902; C. 

torreyi (Motz-Kossowska, 1911); C. microtheca 

Hadzi, 1914; and C. alcoicum Watson, 1993. Due 

to their similarity, several authors regarded most 

of them as conspecific or questionably conspecific 

(Calder 1991). Brinckmann (1959) – working 

with Mediterranean material – examined fertile 

polyps clearly referable to C. microtheca. She 

was able to rear the medusa until the onset of 

gonad development and she allocated her material 

to Mitrocomium cirrata Haeckel, 1879 

(as Eucheilota cirrata), an uncommon medusa 

originally described from the Mediterranean. 

Brinckmann’s medusa agreed reasonably well 

with Haeckel’s medusa, especially in having several 

lateral cirri. The only serious difference was 

the tentacle number which was only four in the 

oldest obtained medusae, while Haeckel’s original 

medusae had 8 tentacles (for a more recent 

description and figure of M. cirratum see Pagès 

et al. 1992). This difference can, however, easily 

be attributed to the younger age of Brinckmann’s 

medusae. The medusae observed by Brinckmann 

were sufficiently old to be allocated to the 

Lovenellidae (sensu Russell 1953, not Bouillon 

1984a). As other medusae of the Lovenellidae 

have either campanulid or lovenellid hydroid 

stages, it seems appropriate to keep the genus 

Mitrocomium with its Halecium-like hydrotheca 

until a comprehensive phylogenetic analysis enables 

recognition of monophyletic groups (see 

also discussion in Calder 1991). 

Because Brinckmann (1959) did not rear her 

medusae to full maturity, Bouillon (1985a: 149) 

doubted that C. microtheca is the hydroid of M. 

153 

cirratum, although earlier he embraced this view 

(Millard & Bouillon 1975: 8) and regarded all 

Campalecium-type hydroids known at that time 

as conspecific with M. cirratum. Boero (1981: 

188) objected to this because he found a Mediterranean 

Campalecium-like hydroid which reportedly 

produced a medusa differing from the one 

described by Brinckmann (1959) and because 

he found that his polyps had nematocysts that 

differed from the ones described by Millard & 

Bouillon (1975). While the umbrellula of the 

polyps of Millard & Bouillon from the Indian 

Ocean had large microbasic mastigophores, 

Boero’s were initially identified as macrobasic 

mastigophores, later corrected to merotrichous 

isorhizas (Boero & Sarà 1987). Unfortunately, 

Brinckmann (1959) did not identify the large 

nematocysts of her polyp. However, I can find no 

significant difference in the figures of the newly 

released medusae depicted by Boero (1981: fig. 

5, as Campalecium medusiferum?) and Brinckmann’s 

medusa (1959: fig. 2e) and I therefore 

suspect that Boero (1981) in fact had M. cirratum. 

But Boero is correct in that his material 

differs from Millard & Bouillon’s (1975) specimens 

from the Indian Ocean and that the latter 

material does not belong to M. cirratum because 

it has different nematocysts. It could belong to M. 

medusiferum or more probably M. simplex. Lifecycle 

studies on Indo-Pacific and Californian 

material are needed to resolve the problem. 

Pictet’s material of H. simplex was infertile 

and it was Ritchie (1910b) who described the 

gonothecae for the first time, this based on material 

from the Mergui Islands. The true nature of 

the gonotheca content of Ritchie’s material was 

later described by Millard & Bouillon (1975), 

who recognized that the gonothecae contained 

medusa buds. 

Unfortunately, no new material of M. simplex 

could be found, but the type material of Halecium 

simplex was re-examined and it proved to have 

many large microbasic mastigophores identical 

to the ones depicted in Millard & Bouillon (1975) 

for their material from the Seychelles. It thus 

appears very probable that Millard & Bouillon 

(1975) as well as Ritchie (1910b) had Mitrocomium 

simplex and not M. cirratum. Future 

studies on living material from the type locality 

of M. simplex must substantiate this, however.

154 

As indicated above, the genus Mitrocomium 

(as defined in Brinckmann (1959) based on Haleciella 

microtheca) presents considerable problems 

not only at the species level, but also at the 

family level. Its hydroids have a hydrotheca that 

associates them with the genus Halecium, while 

their medusae belong to the Lovenellidae (sensu 

Russell). Where known, the hydroids of the family 

Lovenellidae Russell, 1953 are quite disparate, 

some like Eucheilota maculata being of a 

campanulid type (Werner 1968), while others 

are lovenellid with demarcated opercular valves 

(e.g., Lovenella clausa, see Russell 1953 or 

Cornelius 1995a). To account for this, Bouillon 

(1984a, 1985a) placed the genera Eucheilota 

and Lovenella in families of their own and dismissed 

the life cycle of M. cirrata as insufficiently 

known. By this, however, the problem is 

not entirely solved and systems based on the 

medusa stage and the hydroid stage are still incongruent 

(see also Cornelius 1995a: 154, who 

expresses a similar opinion). I consider that 

Mitrocomium, and also the genus Hydranthea 

(see Boero & Sarà 1987), do not belong to the 

Haleciidae but are more closely related to the 

genera Lovenella and Eucheilota, both belonging 

to the family Lovenellidae Russell, 1953 (not 

Bouillon). The positive characters of an intratentacular 

web in the hydroid as well as the lateral 

cirri of the medusa appear to me as more convincing 

synapomorphies than the reduced, Haleciumlike 

hydrotheca. If one considers that the hydrotheca 

in Eucheilota species can be partially 

lost, resulting in hydrothecae strongly resembling 

the ones of Halecium (see fig. 14c in Werner 

1968), then the usefulness of the shape of the 

hydrotheca for delimiting families is severely 

undermined. Such macrotaxonomic problems 

can only be solved in the framework of a comprehensive 

phylogenetic analysis and Mitrocomium 

is presently not removed from the Haleciidae 

as it would cause a major taxonomic instability 

of this family. 

Family Hebellidae 

Remarks 

As discussed in Schuchert (2001), the members 

of the genus Hebella are here placed in the family 

P. SCHUCHERT 

Hebellidae Fraser, 1912 and not the Lafoeidae. 

The species belonging to the Hebellidae have 

recently been revised by Boero, Bouillon & Kubota 

(1997). This revision clearly showed that the 

characters of the hydrotheca alone are mostly 

insufficient to distinguish species. Many members 

of this family release immature medusae that 

must be cultivated to maturity to be identified 

properly, but this has been done for a few species 

only. Migotto & de Andrade (2000) succeeded in 

cultivating the adult medusa of Hebella furax. 

It proved to be a Toxorchis sp. (family Laodiceidae). 

Other Hebellidae release medusae with 

mature gonads or medusoids with gonads on 

the manubrium (genus Anthohebella, see Boero, 

Bouillon & Kubota 1997). It is thus evident 

that Hebellidae species can only be reliably identified 

if the mature gonophores are known. We 

have here a similar situation as for the various 

Campanulina- and Cuspidella-like hydroids (see 

also above under Mitrocomium simplex). 

In the material examined for this study, hebellid 

hydroids were often present on other hydroids, 

sometimes even with gonothecae containing 

immature medusae. For the reasons given 

above, however, they were not identified to species 

level. 

Family Lafoeidae 

Acryptolaria rectangularis (Jarvis, 1922) 

Fig. 13. 

Cryptolaria rectangularis Jarvis, 1922: 335, pl. 24: fig. 3. 

Cryptolaria bulbosa Stechow, 1932: 87. 

Acryptolaria rectangularis. – Millard 1975: 171, fig. 57A– 

D. – Gravier-Bonnet 1979: 17, fig. 4A. – Millard 1980: 

138, fig. 4A. 

Acryptolaria angulata. – Vervoort 1966: 116, fig. 16. – 

Hirohito 1995: 102, fig. 29a–b, pl. 6: fig. B. 


Kei Islands Expedition station 3, at least two stems and 

fragments. 

Description 

Colonies erect, up to 4 cm high, irregularly 

branched, branching primarily in one plane. 

Stem and branches polysiphonic through auxiliary 

tubes covering the hydrotheca-bearing primary 

tube, polysiphonic parts thinning distally,


Fig. 13. Acryptolaria rectangularis (Jarvis, 1922). Part of 

hydrocladium with hydrothecae. – Scale: 0.2 mm 

but even distal branches with at least one auxiliary 

tube. 

Hydrothecae in two rows, alternate, not much 

overlapping, tubular, adnate for ½ of length, 

sharply bent where becoming free, abcauline 

wall at bend with a more or less distinct notch, 

free part of hydrotheca straight, about 0.3 mm 

long, directed slightly upwards or nearly horizontal, 

diameter not much increasing distally, 

diameter at opening 0.15–0.18 mm, rim slightly 

everted, towards base of hydrotheca a ring of 

nodules or a fine diaphragm; hydrotheca without 

internal projection at adcauline side. Nematocysts 

of two sizes: 5 x 3 µm and 23 x 7 µm. 

Gonothecae absent (see Millard 1980 for description). 

Remarks 

Jarvis (1922) distinguished her Acryptolaria 

rectangularis from A. angulata Bale, 1914 by the 

absence of the adcauline projection (dent) into 

the hydrotheca, but Jarvis considered also the 

possibility that both are only two forms of the 

155 

same species. Vervoort (1966) re-examined putative 

type material of A. angulata and allocated 

also South African material to A. angulata even 

though it did not have the dent (“boss” in his 

words) described by Bale (1914b). Because this 

dent represents one of the important diagnostic 

characters to distinguish it from A. rectangularis, 

it must be assumed that Vervoort (1966) regarded 

them as possibly conspecific, although he 

does not explicitly state so in his synonymy. 

Millard (1975) referred Vervoort’s material to A. 

rectangularis. Hirohito’s (1985) material also 

lacked the internal projection and he formally 

synonymized A. angulata, A. rectangularis, and 

A. bulbosa Stechow, 1932. Here, both A. angulata 

and A. rectangularis are treated as separate 

species because both morphotypes were found 

not very far apart. However, I acknowledge the 

possibility that both could be only forms belonging 

to the same species. 

In the material from the Kei Islands there 

was one sample which unambiguously matched 

the descriptions of A. rectangularis as given by 

Jarvis (1922) and Millard (1975) (Fig. 13). 

Distribution 

Southwest Indian Ocean, South Africa, Japan, 

Indonesia (new record), below 100 m depth. 

Type locality: Providence Islands, Indian Ocean, 

228 m. 

Acryptolaria angulata (Bale, 1914) 

Fig. 14. 

Cryptolaria angulata Bale, 1914b: 166, pl. 35: fig. 1. – Bale 

1915: 251. 

Acryptolaria angulata. – Vervoort 1966: fig. 16. 


Syntypes of Cryptolaria angulata, Museum of Victoria, 

Melbourne, F58335, 3 slides. 

Other material examined: 

Kei Islands Expedition station 7, several shoots, up to 2 cm. 

Differential diagnosis 

Similar to A. rectangularis, but hydrothecae 

larger, free part up 0.5–0.7 mm long, opening 

diameter 0.15–0.25 mm, hydrothecae bent nearly 

at right angle, adcauline side with dent projecting 

into lumen, abcauline side becoming free with

156 

marked fold projecting into lumen, without 

refringent nodules at base of hydrotheca. Free 

adcauline side concave. Hydrothecae at end of 

branches different, these with an S-shaped curvature 

(in Indonesian material only, see Fig. 14B). 

Remarks 

The present sample was allocated to A. angulata 

due to the distinct dent in the adcauline wall of 

the hydrotheca and the pronounced fold at the 

bent of the abcauline wall. The Indonesian material 

matched Bale’s type material reasonably 

well, although its hydrothecae are somewhat 

larger and longer (up to 1.5 times) and both the 

adcauline dent and the abcauline fold are more 

pronounced (cf. Fig. 14A and C). The most distal 

hydrothecae of the Indonesian colony (Fig. 14B) 

deviate considerably from the shape of the more 

proximal ones in that they have an S-shaped 

curvature at the place where they become free. 

Such hydrothecae are not present in the type 

material. More material of this rare species is 

needed to evaluate the significance of these differences. 

The difference from the sample identified here 

as A. rectangularis (Fig. 13) appeared too pronounced 

to me to place them both into the same 

species (see above). 

Distribution 

Southern Australia, Indonesia (new record), 

P. SCHUCHERT 

Fig. 14. Acryptolaria angulata (Bale, 1914); A–B, station 7; C, type material from Australia. A. Hydrotheca in polysiphonic 

part, accessory tubules removed. B. Indonesian material, hydrothecae at monosiphonic tip of branch. C. Hydrotheca in 

polysiphonic part. – Scale: A–C = 0.2 mm. 

depth range 182–328 m. Type locality: Great 

Australian Bight, 182 m. 

Acryptolaria conferta (Allman, 1877) 

Fig. 15. 

Cryptolaria conferta Allman, 1877: 17, pl. 12: figs 6–10. – 

von Campenhausen 1896b: 308. 

Fig. 15. Acryptolaria conferta (Allman, 1877). Monosiphonic 

part of distal branch. – Scale: 0.2 mm.


Acryptolaria conferta. – Totton 1930: 164, fig. 19a–b. – 

Ralph 1958: 315, fig. 4a–g. – Millard 1975: 169, fig. 56. 

– Calder 1991: 33, figs, 19–20, synonymy. – Hirohito 

1995: 104, fig. 29c–d, pl. 6: fig. C. – Schuchert 2001: 61, 

fig. 48A–B. 

Acryptolaria conferta var. australis. – Totton 1930: 163, 

figs, 19c–e. – Ralph 1958: 315, fig. 4a–g. – Millard 1964: 

9, fig. 1D, F–G. 

Acryptolaria conferta conferta. – Ramil & Vervoort 1992: 

41, fig. 7a–b. 

Acryptolaria conferta minor Ramil & Vervoort, 1992: 43, 

fig. 8a–c, 9a–c. 

Acryptolaria conferta australis. – Vervoort 1966: 115, fig. 

15. – Rees & Vervoort 1987: 37, fig. 6e. 


Kei Islands Expedition station 7. 

Description 

Colony erect, up to 5 cm, irregularly branched, 

stem and main branches polysiphonic through 

overgrowth of the hydrothecae bearing primary 

tube with auxiliary tubes, polysiphonic part thinning 

towards distal, ends of branches monosiphonic. 

Nodes of primary tube indistinct or absent. 

Hydrothecae alternately arranged on opposite 

sides of primary tube. Hydrothecae tubular, 

smooth, adnate for about half of their length, 

curving outward, outer wall not kinked but 

evenly curved, base of hydrothecae open towards 

axial tube, no diaphragm, diameter of hydrotheca 

slightly increasing distally, diameter at opening 

0.2 mm, margin slightly everted, often renovated. 

Gonothecae absent. 

Remarks 

Millard (1975) commented on the variability of 

this species and following her opinion, no subspecies 

or variants are recognized here. Besides 

nominal subspecies and variants, there are also 

similar species like Acryptolaria pulchella (Allman, 

1888) which are difficult to separate. While 

it seems plausible that there are actually several 

species lumped into A. conferta, the trophosome 

of Acryptolaria offers too few characters for an 

objective separation of morphotypes. However, 

the coppinia of A. conferta from the tropical 

Atlantic and South Africa (see Allman 1877, 

Millard 1975, Calder 1991) lack modified hydrothecae, 

but such modified hydrothecae are 

157 

known to occur in Pacific specimens (Ralph 

1958, Hirohito 1995). Hirohito (1995) found 

both types in Japan. Perhaps this indicates the 

presence of two species. New investigations must 

evaluate the significance of these differences. 

Acryptolaria conferta has already been recorded 

in Indonesian waters by von Campenhausen 

(1896b). 

Distribution 

Circumglobal, usually below 50 m depth. Type 

locality: Off Cojima, Cuba, 823 m. 

Lafoea dumosa (Fleming, 1820) 

Fig. 16. 

Sertularia dumosa Fleming, 1820: 84. 

Lafoea dumosa. – Broch, 1918: 7, fig. 1. – Cornelius 1975b: 

385, fig. 4, synonymy. – Millard 1975: 185. – Rees & 

Vervoort 1987: 40, figs 7–8. – Ramil & Vervoort 1992: 

55. – Cornelius 1995a: 261, fig. 60. – Hirohito 1995: 126, 

fig. 36a–c, pl. 8: fig. A. – Schuchert 2001: 67, figs 54–55. 

Lafoea fruticosa. – Millard 1975: 187, fig. 61A–F. 


Kei Islands Expedition stations: 7. – 46. 

Description 

(Based on Indonesian material) Colonies erect, 

1–2 cm high, polysiphonic, thinning to monosiphonic, 

component tubes parallel, each bearing 

hydrothecae at irregular intervals, arising from 

all sides of branches. 

Hydrothecae tubular, straight, about 0.5 mm 

Fig. 16. Lafoea dumosa (Fleming, 1820); station 7. Hydrotheca. 

– Scale: 0.2 mm.

158 

deep, opening diameter 0.18 mm, cylindrical, 

tapering below into distinct pedicel, pedicel corrugated; 

rim of opening slightly flared; no diaphragm 

or operculum. 

Gonothecae absent (see Millard 1975 or Cornelius 

1995a). 

Remarks 

Lafoea dumosa is here recorded in Indonesian 

waters for the first time. This cosmopolitan 

and extraordinarily variable species has an extensive 

and complicated synonymy (see Cornelius 

1975b, Rees & Vervoort 1987, Schuchert 2001). 

Contemporary authors mostly do not distinguish 

anymore between forms having hydrothecae 

on stalks or sessile ones. However, Schuchert 

(2001) noted that most colonies with sessile 

hydrothecae also have significantly smaller 

isorhiza capsules, suggesting nevertheless the 

presence of two species. The present material 

from Indonesia (Fig. 16) had without exception 

hydrothecae with distinct stalks and the larger 

nematocyst capsule measured around 25 µm in 

length, thus conforming with the common Atlantic 

form. 

Distribution 

Cosmopolitan, mostly below 100 m. Type locality: 

Arbroath, Scotland. 

Zygophylax bifurcata Billard, 1942 

Fig. 17. 

Zygophylax bifurcata Billard, 1942a: 34, figs 1–3. – Rees & 

Vervoort 1987: 79, fig. 13. 


Kei Islands Expedition station 52, 3 shoots on small bivalve. 

Description 

Colonies erect, up to 1 cm, growing on bivalve, 

stem polysiphonic, hydrocladia monosiphonic. 

Primary tube of stem bears hydrothecae and 

hydrocladia. 

Hydrocladia unbranched, alternate, in two 

rows, thin and delicate, nodes indistinct, below 

distal node apophysis for attachment of hy- 

P. SCHUCHERT 

Fig. 17. Zygophylax bifurcata Billard, 1942. A. Part of 

hydrocladium with hydrotheca. B. Apophysis with nematotheca. 

– Scales: A = 0.2 mm; B = 50 µm. 

drotheca. Apophysis occasionally with nematotheca. 

Hydrothecae alternate, with pedicels longer or 

as long as hydrotheca, pedicels about 0.4 mm 

from base to diaphragm, at base some irregular 

annulation, with distinct node delimiting it from 

apophysis. Hydrotheca cylindrical, about 0.3 

mm from diaphragm to opening, tapering at base 

continuously into pedicel; opening diameter 0.12 

mm, often slightly inclined; diaphragm thin. 

Nematotheca tubular, often curved, lower end 

annulated, margin slightly everted. Gonothecae 

not present. 

Remarks 

The present material is only tentatively assigned 

to Z. bifurcata because it lacks one of the diagnostic 

characters: the bifurcated hydrocladia. 

The colonies appear, however, to be juvenile and 

as in other hydroids hydrocladia may branch 

during later development. The identification was 

based on the long pedicels of the hydrothecae. 

Zygophylax bifurcata seems to be the only species 

in this genus with non-recurved primary 

hydrothecae that have pedicels as long or longer 

than the hydrotheca.


Distribution 

Indonesia. Type locality: 8.72°S, 127.28°E, 828 

m (Rees & Vervoort 1987). 

Zygophylax rufa (Bale, 1884) 

Fig. 18. 

Campanularia rufa Bale, 1884: 54, pl. 1 fig. 1. 

Lictorella rufa. – Vervoort & Vasseur 1977: 15, figs 5–8. 

Zygophylax rufa. – Bale, 1914c: 90. – Rees & Vervoort, 

1987: 55. – Gibbons & Ryland 1989: 395, fig. 15. 


Kei Islands Expedition station 53, 1.5 cm fragment of shoot. 

Description 

Colonies erect, a few cm high, stem polysiphonic 

but thin, composed of primary tube and 3 auxiliary 

tubes. 

Hydrocladia strictly pinnate, regularly parallel, 

thin, monosiphonic, without nodes. 

Fig. 18. Zygophylax rufa (Bale, 1884). A. Part of hydrocladium 

with hydrotheca and nematotheca. B. Hydrotheca 

with short apophysis and no node. – Scale: A–B = 0.2 mm 

159 

Hydrothecae alternate, in two rows, the two 

planes forming an angle of

160 

present in shallow waters of the tropical Pacific. 

Although von Campenhausen’s material was 

strictly pinnate, it is also unlikely that it belonged 

to Z. rufa because it was 12 cm high, it had 

branched stems, and the stems were dark-red to 

black. The available data are insufficient to identify 

it unambiguously. 

Distribution 

Great Barrier Reef, French Polynesia, Fiji Islands, 

Kei Islands (new record). Type locality: 

Holborne Island, Great Barrier Reef, Australia. 

Zygophylax sibogae Billard, 1918 

Fig. 19. 

Zygophylax sibogae Billard, 1918: 21 fig. 1. – In part Totton 

1930: 167, fig. 21. – Ralph 1958: 311, fig. 2e–i. – Millard 

1975: 198, fig. 65A–C. – Rees & Vervoort 1987: 72. – 

Hirohito 1995: 144, fig. 45a–d, pl. 9: fig. D. 

Fig. 19. Zygophylax sibogae Billard, 1918; station 33. A. 

Part of stem and hydrocladium; hydrotheca in frontal view. 

B. Hydrotheca in side view. C. Nematotheca on apophysis 

bearing a hydrotheca. – Scales: A–B = 0.2 mm; C = 50 µm. 

P. SCHUCHERT 


Kei Islands Expedition stations: 33. – 46. – 48. – 58; all 

infertile. 

Description 

Colonies erect, up to several cm high; stem polysiphonic, 

sometimes branched, composed of a 

primary tube and auxiliary tubes. Primary tube 

bears hydrocladia, hydrothecae and nematothecae. 

Hydrocladia alternate, monosiphonic, unsegmented, 

bearing alternate hydrothecae on apophyses. 

The two rows of hydrothecae not in one 

plane but borne on anterior surface, with an acute 

angle between them and with the hydrothecae of 

one row rotated so that they slightly face away 

from those of the other row. 

Hydrotheca slender and tubular below the diaphragm, 

then widening and strongly recurved, 

total height 0.6–0.8 mm, depth from upper margin 

to diaphragm 0.3–0.35 mm, diameter of 

opening 0.15 mm. The curved end is trumpetshaped 

and held perpendicular to the axis of the 

lower part of the hydrotheca, resulting in a deep 

fold on one side. Diaphragm well formed, with 

central hydropore. Nematothecae tubular, about 

80–90 µm long, diameter 20 µm, on axial tube, 

accessory tubes at base of hydrocladia, and on 

apophyses of hydrothecae. Not all apophyses 

bear nematothecae. 

Gonothecae not observed (see Billard 1918 

for description; figures are given by Hirohito 

1995). 

Distribution 

Indonesia, New Zealand, South Africa, Japan. 

Type locality: Kei Islands, 5.667°S, 132.433°E, 

310 m. 

Family Campanulariidae 

Clytia linearis (Thornely, 1900) 

Fig. 20. 

Obelia linearis Thornely, 1900: 453, pl. 44: fig. 6. 

In part Obelia bidentata var. – Pictet 1893: 25, pl. 1: figs 20– 

21. [Not Obelia bidentata Clarke, 1875] 

Clytia longicyatha. – Pictet 1893: 28, pl. 2: figs 22–23. [Not 

Obelia longicyatha Allman, 1877] 

In part Clytia serrulata. – Pictet 1893: 30. 

Campanularia gravieri Billard, 1904: 482, fig. 1.


Clytia gravieri. – Billard 1938: 429, figs 1–4. – Millard & 

Bouillon 1973: 51, fig. 7E–G. – Millard 1975: 215, fig. 

71F–H. 

Clytia linearis. – Hirohito 1977: 14, fig. 4. – Cornelius 1982: 

84, fig. 12, synonymy. – Rees & Vervoort 1987: 94. – 

Gibbons & Ryland 1989: 404, fig. 22. – Calder 1991: 62, 

fig. 34, synonymy. – Ramil & Vervoort 1992: 238, fig. 

67b. – Hirohito 1995: 65, fig. 18h–i. – Migotto 1996: 85, 

fig. 16a–b. – Medel & Vervoort 2000: 38, bibliography. 

– Watson 2000: 73, fig. 57D–E. 


Kei Islands Expedition, harbour pier of Ambon, 28 Feb 

1922, 1 m, with gonothecae. – Kei Islands Expedition Stations: 

40, no gonothecae. – 104, no gonothecae. – MHNG 

INVE 25045, as C. longicyatha, Bay of Ambon, Moluccas, 

material described by Pictet (1893), fertile, on Pennaria and 

other hydroids, alcohol and slide material. – MHNG INVE 

31756, Ambon, coll. Pictet and Bedot 1890, colony with 

gonothecae. – MHNG INVE 31757, as Obelia bidentata, 

Ambon, on ascidians, several colonies, material described 

Fig. 20. Clytia linearis (Thornely, 1900); A–B, station 104; 

C, Kei Island Expedition, Ambon harbour. A. Hydrotheca. 

B. Hydrothecal opening seen from above. C. Gonothecae 

with medusae buds. – Scales: A–B = 0.2 mm; C = 0.5 mm. 

161 

by Pictet (1893), with gonothecae. – MHNG INVE 25040, as 

Clytia serrulata, Ambon, material of Pictet (1893), slide and 

alcohol material. 

Description 

Colonies erect, up to 1 cm high, branched, stem 

usually monosiphonic or rarely sparingly polysiphonic. 

Perisarc with short annulated stretches, 

especially at origin of side-branches or hydrothecal 

pedicels, otherwise smooth; branches 

originate at acute angle. 

Hydrothecae on pedicels formed by short 

side-branches, these pedicels usually annulated 

over larger part. Hydrotheca deep, depth 0.75– 

1.0 mm, diameter about 0.35 mm, cylindrical, 

tapering at base, periderm thin and often folded 

or damaged in preserved material; diaphragm 

thin. Margin of hydrotheca with 10–12 narrow 

cusps, between them rounded embayments. Each 

cusp coincides with a sharp longitudinal inwardfold 

that is about 4 times as long as the cusp, 

becoming gradually shallower proximally. The 

folds are as narrow as the cusps and keel-like, the 

periderm is slightly thickened. This produces a 

distinct striation pattern along the hydrotheca 

(Fig. 20A). 

Gonothecae on stem, singly or in pairs, clubshaped, 

up to 1.2 mm long, maximal diameter 0.4 

mm, end truncated, with a more or less distinct 

neck, pedicel annulated. Blastostyle with one or 

two rows of medusae buds. Medusae with hemispherical 

bell and four marginal bulbs. 

Remarks 

Clytia linearis and its extensive synonymy have 

been discussed repeatedly, e.g., by Hirohito 

(1977), Cornelius (1982), and Calder (1991). 

Re-examination of material described by Pictet 

(1893) as C. longicyatha clearly showed that it 

is indistinguishable from C. linearis (Thornely, 

1900) as it is conceived today (e.g., Cornelius 

1982, Calder 1991). Obelia longicyatha Allman, 

1877 is insufficiently known and Cornelius 

(1975a) considered it to be conspecific with O. 

bidentata. 

Also at least some of the material identified 

by Pictet as O. bidentata clearly belongs to C. 

linearis. Pictet’s sample was re-examined for this 

study and it does not match the figure given by

162 

Pictet (1893: pl. 1 fig. 21), which evidently is O. 

bidentata. Because Pictet reports his colony as 

growing on ascidians (“sur une Clavellina”) and 

these animals are still present in the sample, a 

later confusion of samples can be excluded with 

relative certainty. There remains the possibility 

that Pictet examined a single colony no longer 

present in the sample. This seems plausible because 

all remaining colonies on the ascidians are 

without gonothecae, while Pictet (1893) figured 

a colony having a gonotheca containing medusae 

with numerous tentacles. But Pictet mentions 

longitudinal striae on his hydrothecae, which is 

rather typical for C. linearis, but not O. bidentata. 

All colonies growing on the ascidians are clearly 

C. linearis. The jar also contains one separate 

colony, which was originally probably not growing 

on the ascidians. This colony has gonothecae 

with typical Clytia medusae and it is also indistinguishable 

from C. linearis. 

The material identified by Pictet (1893) as 

Clytia serrulata (Bale, 1888) evidently contains 

at least three species. One of them is clearly 

attributable to C. linearis. It has mostly stolonal 

gonothecae that produce four-tentacled medusae. 

Some of the shoots growing on the same 

blade of sea grass belong to a different species; 

their hydrothecae are only half the size of C. 

linearis and the margin is like in Obelia bidentata 

(see below). A third, separate colony on a brown 

alga corresponds to Pictet’s figure 24. The cusps 

of the hydrotheca are often – but not always – 

asymmetric triangles and the colony appears indistinguishable 

from Clytia gracilis (Sars, 1850). 

Campanularia serrulata Bale, 1888 must be regarded 

as unrecognizable because it was based 

on infertile material. Cornelius (1982) synonymized 

it with C. hemisphaerica. 

Clytia linearis has previously been recorded 

in Indonesian waters by Billard (1938, as Clytia 

gravieri). 

Distribution 

Tropical and subtropical waters around the 

world (Medel & Vervoort 2000). Type locality: 

Blanche Bay, New Britain, Papua New Guinea. 

Clytia trigona Pictet, 1893 

Fig. 21. 

P. SCHUCHERT 

Fig. 21. Clytia trigona Pictet, 1893; after slide preparation of 

type material. A. Hydrotheca; note that the calyx is somewhat 

compressed. B. Part of stem showing typical arrangement 

of gonothecae in sets of three. C. Gonothecae with 

medusae buds. – Scales: A, C = 0.2 mm; B = 0.5 mm. 

Clytia trigona Pictet, 1893: 33, pl. 2 figs 28–29. 


MHNG INVE 25043, slide and alcohol material, alcohol 

material badly preserved. 

Diagnosis 

Like Clytia linearis (Thornely, 1900), but 2–3 

gonothecae grouped together, gonothecae 0.8– 

0.9 mm long, hydrotheca depth 0.5–0.7 mm. 

Remarks 

Clytia trigona closely resembles C. linearis and it 

is quite possible that they are conspecific. Clytia 

trigona is here kept separate on account of the 

gonothecae, which develop along the stem in 

groups of two or three; a few are also solitary. I


have never seen C. linearis with groups of more 

than 2 gonothecae. Additionally, the hydrothecae 

were significantly shorter than in specimens of C. 

linearis of the Bay of Ambon. If new material 

reveals intermediate forms, so that in C. linearis 

groups of up to three gonothecae can occur 

besides solitary ones, the younger C. linearis 

(Thornely, 1900) should be synonymized with 

Clytia trigona Pictet, 1893. This would be somewhat 

awkward, as a widely known and used 

name would be replaced by a virtually unknown 

one. 

Distribution 

Known from its type locality only: Bay of Ambon, 

Moluccas, Indonesia. 

Fig. 22. Clytia arborescens Pictet, 1893; after type material. 

A. Hydrotheca in oblique view. B. Monosiphonic part with 

gonotheca and hydrotheca. – Scale: 0.2 mm. 

163 

Clytia arborescens Pictet, 1893 

Fig. 22. 

Clytia arborescens Pictet, 1893: 34, pl. 2: figs 30–31. – 

Billard 1933: 8, fig. 2. – Millard & Bouillon 1973: 50, 

fig. 7A-D. – Medel & Vervoort 2000: 30, figs 7–8, 

bibliography. 

Laomedea arborescens. – Leloup 1937: 20, fig. 10. 


MHNG INVE 25044, alcohol and slide preparation, growing 

on stem of tubularid hydroid. 


Kei Islands Expedition station 95, Sunda Strait, one 3 cm 

colony highly polysiphonic, without gonothecae, identification 

uncertain. 

Description 

Colony erect, up to 2 cm high, in same colony 

monosiphonic or highly polysiphonic stems, up 

to 20 tubes per polysiphonic stem, stem branching, 

branches also polysiphonic, thinning to 

monosiphonic. Perisarc with short annulated 

stretches, especially at origin of side-branches or 

hydrothecal pedicels, otherwise smooth, monosiphonic 

branches originate at acute angles. 

Hydrothecae on pedicels formed by short 

side-branches, these usually almost entirely annulated. 

Hydrotheca conical, about 0.45–0.55 

mm deep, diameter 0.25–0.3 mm, with about 12– 

14 sinusoid cusps, these about 20 µm high, symmetric, 

embayments between them rounded. 

Each cusp coincides with a longitudinal inwardfold 

that is about 3 times as long as the cusp, 

becoming gradually shallower downwards. The 

folds produce a striation pattern originating lateral 

to the cusps (Fig. 22A–B). A thin diaphragm 

near base of hydrotheca, slightly oblique or horizontal. 

Gonothecae borne singly on stem, usually 

next to a hydrothecal pedicel. Gonotheca about 

0.8–1.2 mm, club-shaped, with flat distal end, 

without neck, diameter in middle of gonotheca 

about 0.25 mm, at end 0.18 mm. Blastostyle in 

gonotheca forming a single row of up to 6 

medusae buds. Medusae with hemispherical bell 

and four bulbs. 

Remarks 

With its inward folds along the hydrotheca, Clytia 

arborescens somewhat resembles C. linearis, 

but it can be distinguished from the latter by its

164 

highly polysiphonic stem (although also monosiphonic 

ones occur in the same colony), the 

shorter hydrothecae, and the broad, rounded 

cusps. Clytia linearis typically has pointed cusps 

and the longitudinal inward-fold are very narrow, 

giving a much more distinct longitudinal 

striation (see Fig. 20). Recently, Medel & Vervoort 

(2000) assigned material from Madeira to 

this species. Their material closely resembles the 

Pacific material, but has more pointed cusps 

which are apparently inclined to one side, and the 

gonotheca has a slight neck formation and lacks 

an annulated pedicel. Moreover, Medel & Vervoort 

do not mention longitudinal folds of the 

hydrothecae in their material. 

Distribution 

Indonesia, Vietnam, Seychelles, Gulf of Suez, 

Gulf of Akaba, Madeira (after Medel & Vervoort 

2000). Type locality: Port of Ambon, Moluccas, 

Indonesia. 

Clytia gracilis (M. Sars, 1850) 

Fig. 23. 

Laomedea gracilis M. Sars, 1850: 138. 

Clytia gracilis. – Stechow & Müller 1923: 461. – Cornelius 

Fig. 23. Clytia gracilis (M. Sars, 1850); MHNG INVE 

25040. Hydrotheca and gonothecae. – Scale: 0.2 mm. 

P. SCHUCHERT 

& Östman 1986: 163. – Calder 1991: 54, fig. 31, synonymy. 

– Ramil & Vervoort 1992: 235, fig. 67a. – 

Cornelius 1995b: 246, fig. 56. – Hirohito 1995: 63, fig. 

18c–g. – Migotto 1996: 81, fig. 15c. – Medel & Vervoort 

2000: 32, bibliography. 

In part Clytia serrulata. – Pictet 1893: 30, pl. 2: figs 24–25. 


MHNG INVE 25040, as Clytia serrulata, Ambon, material 

of Pictet (1893), slides and alcohol material. 

Description 

Colony stolonal or sparingly branched (1–3 

times), height up to 5 mm. Perisarc smooth with 

annulated stretches. 

Hydrotheca campanulate, depth 0.6 mm, diameter 

0.33 mm, perisarc thin, diaphragm at base 

thin but distinct, margin with 12 large, pointed 

teeth, separated by rounded embayments. The 

teeth are often asymmetric (tilted) with one side 

almost vertical and the other oblique. The margin 

in the embayments is slightly everted. 

Gonothecae arise on stolons and stems, oblong 

barrel-shaped, at distal end an indistinct 

neck formation for the aperture. Blastostyle produces 

medusae with a hemispherical bell and 

four bulbs. 

Remarks 

As discussed under C. linearis, part of the material 

described by Pictet (1893) as C. serrulata 

(Bale, 1888) can be assigned to C. gracilis, a fact 

already suspected by Calder (1991). The material 

matched rather well material from the North Atlantic 

(Schuchert 2001), only the hydrothecae are 

somewhat smaller and apparently not all cusps 

are asymmetric (tilted). 

Clytia gracilis has previously been reported 

for Indonesian waters by Stechow & Müller 

(1923). 

Distribution 

Circumglobal in temperate and tropical waters. 

Type locality: Lofoten Islands, Norway. 

Obelia bidentata Clarke, 1875 

Fig. 24 

Obelia bidentata Clarke, 1875: 58, pl. 9: fig. 2. – Cornelius 

1975a: 260, fig. 2. – Cornelius 1982: 113, table 4, 

synonymy. – Gibbons & Ryland 1989: 405, fig. 23. –


Fig. 24. Obelia bidentata Clarke, 1875; hydrothecae and 

gonotheca. – Scale: 0.2 mm. 

Calder 1991: 70, fig. 37, synonymy. – Ramil & Vervoort 

1992: 241, fig. 68a–b. – Cornelius 1995b: 292, fig. 68. – 

Migotto 1996: 87, fig. 16c. – Medel & Vervoort 2000: 

46, fig. 12, bibliography. 

Obelia bicuspidata Clarke, 1875: 58, pl. 9: fig. 1. – Fraser 

1944: 153, fig. 125. – Millard & Bouillon 1973: 56. – 

Millard 1975: 226, fig. 75C–D. – Hirohito 1995: 71, fig. 

21a–b, pl. 5: fig. A. 

In part Obelia bidentata var. – Pictet 1893: 25, pl. 1: figs 20– 

21. 

Gonothyraea longicyatha Thornely, 1900: 454, pl. 44: fig. 

4–4a. 


Kei Islands Expedition station 81, with gonothecae. 

Description 

Colonies erect, up to 4 cm high, arising from a 

tangled mass of stolons anchoring the colony in 

the sediment. Main trunk forked several times, 

polysiphonic, thinning to monosiphonic, branching 

irregular, primarily in one plane. Short 

stretches of annulations alternating with long 

smooth regions of perisarc. 

Hydrothecae on short, annulated pedicels; hy- 

165 

drothecae set relatively dense. Hydrotheca deep, 

conical, often slightly asymmetric in lower region 

through slightly bulging wall, depth 0.7– 

0.75 mm, diameter at opening 0.30–0.33 mm, 

diaphragm thin, may be oblique, calyx margin 

with about 12 bimucoronate cusps, embayments 

all U-shaped, embayments not or only slightly 

everted. Each cusp with two very pointed teeth, 

separated by a deep embayment, depth of this 

embayment about 2/3 of the intercusp embayments. 

There are no longitudinal lines along the 

hydrotheca. 

Gonothecae borne singly along stem, comparatively 

small, length around 0.8 mm, with 

annulated pedicel, main body flattened, clubshaped 

in broad view, end truncated, without 

neck formation. Blastostyle with medusa buds, 

most advanced with numerous short tentacles. 

Remarks 

The gonothecae seen in the present specimen of 

O. bidentata were all flattened. Similarly compressed 

gonothecae were noted for this species 

by Hirohito (1995) and Thornely (1900, as Gonothyraea 

longicyatha), although the latter attributed 

this to the fixation. Although this is a reasonable 

explanation, living Pacific material should 

be examined to confirm this. In the present specimen, 

the regularity of the compression, even in 

immature gonothecae, led me to suspect that this 

compression is a natural feature. Perhaps it is 

confined to some Pacific populations. 

The gonothecae of O. bidentata are mostly 

described as having no neck at their end, but 

Gibbons & Ryland (1989) and Cornelius (1995b) 

depict and describe specimens having a distinct 

neck with a much smaller diameter than the main 

body of the gonothecae, resembling gonothecae 

found in many other Obelia species. 

As discussed under C. linearis, material described 

by Pictet (1893) as O. bidentata is mostly 

referable to C. linearis, although the figures 

given by Pictet (1893) are clearly of O. bidentata. 

Distribution 

Circumglobal in temperate to tropical waters 

(Medel & Vervoort 2000). Type locality: Wharf 

piles of Greenport, Long Island, New York, 

USA.

166 

Fig. 25. Diphasia digitalis (Busk, 1852); station 72. A. Part 

of stem and hydrocladium. B. Gonotheca. – Scale: A–B = 0.5 

mm. 

Family Sertulariidae 

Diphasia digitalis (Busk, 1852) 

Fig. 25. 

Sertularia digitalis Busk, 1852: 393. 

Desmoscyphus longitheca Allman, 1877: 26, pl. 14: figs 3– 

6. – Nutting 1904: 111. 

Desmoscyphus acanthocarpus Allman, 1888: 73, pl. 35: fig. 

2a–c. – Nutting 1904: 111. 

Nigellastrum digitale. – Mammen 1965: 57, fig. 89. 

Diphasia digitalis. – Nutting 1904: 110, pl. 30: figs 2–7. – 

Bale 1884: 101, pl. 9: figs 3–5. – Billard 1925b: 209. – 

Vervoort 1959: 254, fig. 22. – Vervoort 1968: 37, fig. 17. 

– Millard & Bouillon 1973: 67, fig. 9A. – Millard 1975: 

257, fig. 85E. – Watson 2000: 14, fig. 10A–B. 


Kei Islands Expedition stations: 18, fertile. – 67. – 68. – 71, 

fertile. – 72, fertile. – 90, fertile. – 104. – 107, fertile. – 110. 

Description 

Colonies erect, pinnate, 3–6 cm high. Main stem 

mostly unbranched, occasionally branched, with 

two rows of hydrothecae. Hydrocladia alternate, 

somewhat irregular in distribution and length. 

Hydrothecae in opposite pairs, consecutive 

pairs mostly overlapping or very close. In lower 

P. SCHUCHERT 

region of the stem members of a pair of hydrothecae 

placed on lateral sides and not contiguous 

with one another; in distal region and on hydrocladia 

members of a pair placed on anterior surface 

and contiguous with one another, the two 

rows forming an angle that is much less than 

180°. Hydrotheca about 0.8 mm deep, 0.3 mm 

broad, adnate for ¾ to entire length, distal part 

curved slightly away, cross section rounded in 

basal part, distinctly pentagonal at distal end, 

with lateral longitudinal crease lines, sometimes 

also a short median crease line on abcauline wall 

beginning at margin of hydrotheca, margin untoothed, 

on adcauline side a broad and deep 

emargination. No internal cusps or ridges. Operculum 

single, large, attached to adcauline rim of 


Gonothecae on stem, spindle shaped, 2 mm 

long, diameter 0.6 mm, with numerous short, 

stout spines in 10–12 rows, 10–12 spines per row. 

Hydranths without abcauline blind-sac. 

Remarks 

Almost all examined colonies had characteristic 

blackish pigment granules in the epidermis of the 

coenosarc and the tissue covering the inside of 

the hydrotheca. Bale (1884) described the colour 

of the colony as grey to almost black. 

Distribution 

Circumglobal in tropical and subtropical waters. 

Type locality: Prince of Wales Channel, Torres 

Strait, Australia, 16 m. 

Diphasia mutulata (Busk, 1852) 

Fig. 26. 

Sertularia mutulata Busk, 1852: 391. 

Diphasia mutulata. – Bale 1884: 101, pl. 9: figs 6–9. – 

Ritchie 1910a: 12, pl. 4: fig. 3. – Billard 1933: 16, fig. 6, 

pl. fig. 4. – Watson 2000: 12, fig. 9A–G. 

?Diphasia mutulata. – Thornely 1904: 118, pl. 2: fig. 6 [? = 

Diphasia thornelyi Ritchie, 1909]. 

?Diphasia thornelyi Ritchie, 1909: 525. – Ritchie 1910a: 13, 

pl. 4: figs 4–5. – Jäderholm 1919: 16, pl. 4: figs 2–3. – 

Billard 1925b: 215, fig. 54. 

Diphasia thornelyi. – Jäderholm 1919: 16, pl. 4 figs 2–3. 

Nigelastrum mutulatum. – Stechow & Müller 1923: 468. – 

Mammen 1965: 56, fig. 88. 


Kei Islands Expedition, Tual, Kei Islands, 1–2 m, 23 Mar


Fig. 26. Diphasia mutulata (Busk, 1852); Tual, Kei Islands. 

A. Part of stem with long hydrothecae, transparent side view. 

B. Oblique view of part of stem, shown opaque. C. Short 

form of hydrothecae. D. Female gonotheca. – Scale: A–D = 

0.2 mm. 

1922, fertile female, on Aglaophenia cupressina Lamouroux, 

1816. – Kei Islands Expedition, Tual, Kei Islands, 2 m, 

21 Mar 1922, infertile, on Aglaophenia cupressina Lamouroux, 

1816, some stems with opposite and alternate hydrothecae. 

– Kei Islands Expedition station 67, infertile, on 

Monoserius pennarius (Linnaeus, 1758). 

Description 

Colonies forming simple stems without hydro- 

167 

cladia, rarely branched once, up to 1 cm high, 

occasionally with terminal stolonization, nodes 

occasionally present. Hydrorhiza tubular, creeping 

on host hydroid. 

Hydrothecae normally opposite, occasionally 

in more distal part alternate, successive hydrothecae 

not overlapping in present material, the 

opposite pairs placed on lateral sides of stem and 

not contiguous, the pair not or only slightly displaced 

towards one side of stem. Hydrotheca 

at base somewhat rectangular in cross-section, 

distal half tubular, outer side rounded, without 

sharp edges, curved outward, abcauline length 

0.45–0.5 mm, diameter at opening 0.16–0.2 mm, 

adcauline side adnate for ¾ of length, some hydrothecae 

almost completely adnate. Abcauline 

wall of hydrotheca in about middle with a transverse 

intrathecal semicircular ridge, this ridge 

very variable between hydrothecae, may be absent. 

Adcauline margin of hydrotheca with a 

broad emargination; sometimes on each side of 

hydrotheca near distal end a short, weak crease 

line. One large adcauline operculum. 

Gonothecae near base of stem, two per shoot 

in present material, egg-shaped, 0.8 mm long, 

0.55 mm diameter, aperture on distinct neck, 

distal half with up to 12 short, broad, spines 

directed towards distal end of gonotheca. 

Remarks 

Watson (2000) examined material from northern 

Australia and found that this population of Diphasia 

mutulata had colonies producing two distinguishable 

stem forms. Watson named these 

two forms mutulata and heurteli morph. The 

heurteli morph had shorter, contiguous hydrothecae. 

Although there were no intermediate 

forms, both stem types grew from the same 

stolons. Watson therefore synonymized Diphasia 

mutulata and D. heurteli Billard, 1924. Although 

I think she might be correct, Billard’s 

(1924) first description of D. heurteli shows 

hydrothecae somewhat different from Watson’s 

heurteli morph. Billard’s figure (1924, fig. 2A) 

appears indistinguishable from the hydrothecae 

observed here (Fig. 26A). Billard (1924) based 

his description of D. heurteli on infertile material 

and only Millard (1975) found gonothecae in 

a population from the type locality. Millard’s

168 

gonothecae were triangular with a wide distal 

aperture, thus differing from the ones repeatedly 

observed in D. mutulata (Fig. 26D), which are 

egg-shaped and have their opening on a distinct 

neck. Watson (2000), assumed that Millard’s 

gonothecae were immature. Although possible, 

I somewhat doubt this, because Millard could 

identify the sex of her specimen and she had 

several gonothecae at hand. New fertile material 

from the type locality of D. heurteli must be 

examined before further conclusions can be 

drawn. Therefore, following Millard (1975), 

Diphasia heurteli is here kept separate from 

D. mutulata, although they could prove to be 

conspecific. 

The hydrothecae in the present material also 

showed some variation within the same stem 

(Fig. 26A, C), but two distinguishable morphs 

were not discernible. 

Thornely’s (1904) material identified as D. 

mutulata had alternate hydrothecae and Ritchie 

(1909) referred it to Diphasia thornelyi Ritchie, 

1909. The alternate hydrothecae seem to be the 

only reliable diagnostic character to distinguish 

D. thornelyi from D. mutulata. However, Ritchie 

(1909) and Billard (1925b) mention that occasionally 

some hydrothecae can be paired in D. 

thornelyi. Jäderholm (1919) identified material 

from Japan as D. thornelyi despite that it had 

opposite hydrothecae throughout. In one of the 

colonies examined for the present study, opposite 

and alternate arrangements occurred within the 

same stem. I therefore suspect that D. thornelyi is 

only a form of D. mutulata. I refrained from 

synonymizing them definitively because I have 

not seen the type material of D. thornelyi. 

Besides the two mentioned species, there are 

at least seven more Diphasia species known 

from Indonesia: D. cauloatheca Billard, 1920b; 

D. cristata Billard, 1920b; D. densa (Stechow, 

1923); D. minuta Billard, 1920b; D. orientalis 

Billard, 1920b; Diphasia mutulata; and D. scalariformis. 

The latter two species were also found 

in the present material. 

Diphasia mutulata is easily distinguishable 

from D. scalariformis. Diphasia scalariformis 

has overlapping, quite straight, rectangular hydrothecae 

with sharp edges that are distinctly 

displaced towards one side of the branch surface. 

D. mutulata has its hydrothecae on the lateral 

P. SCHUCHERT 

sides of the branch, they are mostly not contiguous, 

they are more curved and their distal end is 

tubular without sharp edges. 

Diphasia digitalis is distinguishable from 

D. mutulata through its pentagonal cross-section 

of the distal part of the hydrothecae, the much 

larger hydrothecae, the absence of intrathecal 

processes, the branched colonies, and the larger 

gonothecae with numerous spines. 

Diphasia cauloatheca forms large, pinnate 

colonies and has stems without hydrothecae. Diphasia 

cristata is unbranched and has a characteristic 

pattern of sharp ridges on its hydrothecae 

and also on the rear side of the stem. Diphasia 

orientalis resembles D. mutulata, but its female 

gonothecae have complicated processes and 

the hydrotheca has a median ridge flanked by two 

channel-like concavities of the hydrothecal wall. 

Diphasia densa is not sufficiently well known. 

Diphasia minuta forms small (5 mm) shoots and 

has smooth gonothecae. Otherwise it closely resembles 

D. mutulata and it may in fact be only a 

form of this species 

Distribution 

Northern Australia, Indonesia, Andaman Sea, 

Red Sea. Type locality: Prince of Wales Channel, 

Torres Strait, Australia, 16 m. 

Diphasia scalariformis Kirkpatrick, 1890 

Fig. 27. 

Diphasia scalariformis Kirkpatrick, 1890: 609, pl. 15: fig. 3. 

– Jäderholm 1903: 287. – Billard 1925b: 216, figs 55–56. 

Nigellastrum mutulatum. – Stechow & Müller 1823: 468. – 

Billard 1925b: 216, footnote. 


Kei Islands Expedetion stations: 15. – 16. – 18. – 26. – 30. – 

Kei Island Expedition, Sulawesi, Ujungpandang, Samalon 

Island, 5 m, 28 Jun 1922; colonies of all stations with 

gonothecae and growing on Lytocarpia angulosa (Lamarck, 

1816). 

Description 

Colonies growing on Lytocarpia angulosa, 

shoots straight, without hydrocladia or with some 

irregular side-branches, 2–5 cm high. 

Hydrothecae in opposite pairs, each pair contiguous 

on one side of shoot, separate on rear, 

thus hydrothecae shifted to anterior side of


Fig. 27. Diphasia scalariformis Kirkpatrick, 1890; A–C, E, 

station 30; D, station 18. A. Two pairs of hydrothecae in 

anterior view, shown opaque. B. Hydrothecae in posterior 

view, shown transparent. C. Hydrocladium with female 

gonothecae having short spines, side view. D. Variant with 

longer and more recurved hydrothecae, left hydrotheca in 

side view. E. Female gonotheca with long spines. – Scale: 

A–E = 0.2 mm. 

169 

hydrocladium, the two rows of hydrothecae 

forming an angle smaller then 180°. Successive 

hydrothecae overlapping slightly. Hydrotheca 

quadrangular with sharp edges, distal half 

slightly curved outward, basal part straight, anterior 

and lateral sides of hydrotheca nearly plane, 

abcauline side 0.5–0.6 mm, adcauline side 0.35– 

0.45 mm, adcauline side adnate for most of its 

length, opening of hydrotheca oblique, lateral 

margin S-shaped, anterior margin slightly depressed 

and thus forming two lateral marginal 

cusps, edges of hydrotheca reinforced by perisarc 

thickenings, on abcauline side slightly above 

middle an intrathecal shelf or flap projecting 

upwards into hydrotheca. Stem and branches 

without nodes. 

Gonothecae in a single row along anterior side 

of stem, very numerous, arising below hydrothecal 

pairs. Gonotheca egg-shaped, 0.45 mm 

long, diameter 0.3 mm, lateral and abcauline side 

with up to 12 spines, some colonies have blunt 

and shallow spines, some pointed and long ones, 

aperture of gonotheca at distal end on short neck. 

Female gonothecae with more than 50 small 

eggs, diameter of egg about 25 µm. Hydranths 

small, about 12 tentacles, without abcauline 

blind-sac. 

Remarks 

The tightly set quadrangular hydrothecae and the 

small gonothecae make this species immediately 

recognizable. Furthermore, in Indonesia this species 

only grows on the hydroid Lytocarpia 

angulosa (Lamarck, 1816). Jäderholm reported 

this species from southern Japan, growing on L. 

secundus (Kirchenpauer, 1872), a subjective 

synonym of Monoserius pennarius (Linnaeus, 

1758) (see Ritchie 1910a). 

Diphasia digitalis is readily distinguishable 

from D. scalariformis through its pentagonal 

cross-section of the distal part of the hydrothecae, 

the much larger hydrothecae, the absence 

of intrathecal processes, the pinnately branched 

colonies, and the larger gonothecae with numerous 

spines. The differences from D. mutulata are 

given under the latter species. 

Billard (1925b) found that the male gonothecae 

of D. scalariformis has more pointed 

spines. Perhaps this correlation was due to con-

170 

tingency because of the small number of specimens. 

In the present material also female gonothecae 

with very pointed spines could be found 

(Fig. 27E). 

Distribution 

Torres Strait, Indonesia, southern Japan. Type 

locality: Torres Strait, Australia. 

Dynamena crisioides Lamouroux, 1824 

Fig. 28. 

Dynamena crisioides Lamouroux, 1824: 613, pl. 90: figs 

11–12. – Billard 1925b: 181, figs 36–37, pl. 7: fig. 21. – 

Vervoort, 1941: 209. – Vervoort 1959: 260, fig. 27a–b. – 

Vervoort 1968: 38, fig. 18. – Millard & Bouillon 1974: 

32, fig. 6D. – Millard 1975: 263, fig. 87A–F. – Rees & 

Vervoort 1987: 103. – Gibbons & Ryland 1989: 410, fig. 

28. – Calder 1991: 89, figs 47–48, synonymy. – Hirohito 

1995: 170, fig. 55a–b. – Migotto 1996: 60, fig. 11e–g. – 

Medel & Vervoort 1998: 21, synonymy and bibliography. 

Dynamena tubuliformis Marktanner-Turneretscher, 1890: 

238, pl. 4: fig. 10. 

Sertularia Vegae. – Pictet 1893: 44, pl. 2: figs 37–38 [not 

Thuiaria vegae Thompson, 1887]. 

Not Sertularia tubuliformis. – Broch 1918: 132, fig. 71 [= S. 

similis (Clarke, 1876)]. 

?Pasythea griffini Hargitt, 1924: 498, pl. 6 fig. 25. 

Sertularia crisioides var. gigantea Billard, 1925a: 651. – 

Billard 1925b: 186, pl. 8: fig. 24. – Leloup 1930b: 7, figs 

4–5, pl. 1: fig. 2. – Vervoort 1941: 210, fig. 4. 

Sertularia crisioides var. alternata Billard, 1925a: 652. – 

Billard 1925b: 187, fig. 39, pl. 7: fig. 22. – Vervoort, 

1941: 213. 

Sertularia crisioides var. peculiaris Billard, 1925b: 185, fig. 

38. 


Kei Island Expedition, Banda Islands, Waling, 20 m, 11 Jun 

1922 – Kei Islands Expedition, Ujungpandang, Samalon 

Island 35 m, 28 Jun 1922 – Kei Islands Expedition, Kei 

Islands, Tual, 1–2 m, 23 Jun 1922, with gonothecae. – 

MHNG INVE 31974, Sertularia vegae, Ambon, material of 

Pictet (1893). 

Description 

Colonies erect, monosiphonic, 2–5 cm in present 

material, pinnate with alternate hydrocladia. 

Stem unbranched, zigzag, with short basal 

athecate part terminated by a transverse node. 

Nodes on stem irregular, mostly indistinct. Stem 

with two lateral rows of alternate apophyses for 

the hydrocladia, apophyses long, delimited by 

node from hydrocladium. Hydrothecae of stem 

P. SCHUCHERT 

Fig. 28. Dynamena crisioides Lamouroux, 1824; Banda 

Islands. A. Silhouette of a shoot. B. Part of stem and 

hydrocladia. C. Group of hydrothecae from hydrocladium. 

D. Gonotheca in side view. – Scales: A = 1 cm; B, D = 0.5 

mm; C = 0.2 mm. 

in two lateral rows; one hydrotheca in axil of 

apophysis and a variable number (2–3) of subopposite 

hydrothecae between two apophyses. 

Hydrocladia unbranched, divided by straight 

nodes into internodes which bear a variable num-


ber (normally 2–3) of subopposite pairs of hydrothecae. 

The two rows of hydrothecae in plane 

of ramification of shoot. Members of hydrothecal 

pairs not contiguous, consecutive hydrothecae of 

an internode mostly overlapping and forming 

groups. 

Hydrotheca tubular, adnate for ¾ to 9/10 of 

adcauline length, then bent outwards, 0.40–0.45 

mm in abcauline height and 0.10–0.12 mm in 

marginal diameter; opening-plane parallel to axis 

or nearly so, margin with two broad and triangular 

lateral teeth slightly below middle and one 

smaller adcauline tooth. Below abcauline margin 

a perisarc thickening. Operculum composed of 

two valves, upper valve like a gabled roof. 

Hydranth with 10–12 tentacles, without abcauline 

blind-sac. 

Gonothecae arise on stem below hydrothecae, 

ovate, 1.4 mm long, thickest part 0.8 mm diameter, 

wall irregularly undulated, opening on a 

slightly curved and flaring neck, neck not in 

middle and thus rendering gonothecae bilateralsymmetric. 

Remarks 

This species can show considerable variation. 

The extent of variation is well described in Millard 

(1975). Billard (1925a, 1925b) named some 

of these variants, but later authors, especially 

Millard (1975), found them to be connected 

by all possible intermediate forms. The present 

samples conformed with Billard’s normal form. 

Pictet’s (1893) material of Sertularia vegae belongs 

to S. crisioides. It is a form with more 

distant hydrothecae. 

Re-examination of the type material of Pasythea 

griffini Hargitt, 1924 (USNM 42656) 

showed it to closely resemble D. crisioides, but 

the few hydrothecae are apparently arranged in 

opposite pairs. The gonothecae are identical to 

the ones described here for D. crisioides. Although 

Hargitt’s species likely belongs to D. 

crisioides, the available type material could not 

provide conclusive evidence. 

There exist at least five more Dynamena species 

in Indonesian waters: Dynamena moluccana 

(Pictet, 1893), 1858; D. fissa Thornely, 1904; D. 

heterodonta (Jarvis, 1922); Dynamena mertoni 

(Stechow, 1923); and D. quadridenta (Ellis & 

171 

Solander, 1786). Dynamena crisioides is readily 

distinguished from all of them through its subopposite 

hydrothecae. In the other species they 

are always strictly opposite. Additional descriptions 

of the other Indonesian species of Dynamena 

can be found in Billard (1925b), Millard 

(1975), and Watson (2000). 

Distribution 


Type locality: Moluccas, Indonesia. 

Dynamena moluccana (Pictet, 1893) 

Fig. 29. 

Sertularia divergens. – Bale, 1884: 81, pl. 5: fig. 3, pl. 19: 

fig. 16. [Not Dynamena divergens Lamouroux, 1816] 

Sertularia moluccana Pictet, 1893: 50, pl. 2: figs 42–43. – 

Billard 1925b: 189. 

?Sertularia complexa. – Pictet 1893: 47, pl. 2: figs 39–40. – 

Billard 1925b: 189. [Not Sertularia complexa Clarke, 

1879, = Dynamena disticha (Bosc, 1802)] 

Desmoscyphus palkensis Thornely, 1904: 119, pl. 2: fig. 

7A–B. 

Dynamena cornicina. – Billard 1925b: 188, fig. 40, pl. 7: fig. 

23. – Billard 1933: 14, fig. 5, pl. fig. 3. – Vervoort 1941: 

206, fig. 3. – Millard & Bouillon 1973: 68. – Cooke 

1975: 94, pl. 3: figs 3–4. – Millard 1975: 261, fig. 86A– 

E. – Gibbons & Ryland 1989: 408, fig. 27. – Vervoort 

1993: 108. 

Not Dynamena cornicina McCrady, 1859: 204. – Genzano 

1992: 144, figs 5–6. – Hirohito 1995: 167, fig. 54a–g. 

[All = Dynamena disticha (Bosc, 1802)] 

Sertularia cornicina var. pinnata Jarvis, 1922: 339. 

Dynamena exigua. – Hirohito 1995: 172, fig. 55c–g. [Not 

Sertularia exigua Allman, 1877, = D. disticha] 


MHNG INVE 25031, holotype of Sertularia moluccana, 

slides, without gonotheca. 


MNHG INVE 25033, as Sertularia complexa, slide and 

alcohol material of Pictet (1893), with gonothecae. – Kei 

Islands Expedition, Neira Island, Banda Islands, 1 Jun 1922, 

20 m, sand bottom, 5 damaged plumes, no gonothecae. – For 

comparisons: Dynamena disticha, MHNG INVE 29754 and 

27132, both from Cala Murada, Mallorca, 1–2 m, coll. 1999 

and 2000, with gonothecae. – Dynamena pumila, MHNG 

INVE 29033, Sandgerdi, Iceland (see Schuchert 2001). 

Description 

Colonies erect, 1–3 cm high (reportedly up to 6 

cm), loosely pinnate. Stolons creeping, tubular.

172 

Fig. 29. Dynamena moluccana (Pictet, 1893); A–B, after 

holotype; C, after MHNG INVE 25033, unbranched form. 

A. Stem segments and basal parts of hydrocladia. B. Pair of 

hydrothecae from hydrocladium. C. Gonotheca. – Scales: A 

= 0.5 mm; B–C = 0.2 mm. 

Stems zigzag, divided by transverse nodes, segment 

ends bulging. Each stem segment with three 

hydrothecae and an apophysis for the hydrocladium; 

apophysis short, near lower end of segment, 

in its axil a hydrotheca, this hydrotheca 

free for most of its length and strongly recurved, 

P. SCHUCHERT 

the two remaining hydrothecae more distal and 

subopposite. 

Hydrocladia alternate, first segment without 

hydrotheca, with proximal transverse node and a 

distal, very oblique hinge-joint node, nodes after 

first hydrothecal pair transverse or slightly oblique. 

Hydrothecae in two lateral rows, somewhat 

displaced to one side of hydrocladium, 

strictly opposite, each pair contiguous on anterior 

side, separate on rear side, consecutive hydrothecae 

of one row well separated. 

Hydrotheca tubular, adnate for 2/3 of its 

length, adcauline side sharply bent where becoming 

free, abcauline side nearly straight, length 

0.4–0.45 mm, adcauline side about 0.7 mm, diameter 

of opening 0.18–0.2 mm, angle of opening-plane 

nearly parallel to segment axis or 

slightly tilted towards above, margin with two 

lateral cusps. Perisarc of hydrotheca, especially 

distal end, thin, very delicate and often damaged; 

lateral cusps frequently not observable. Hydranths 

relatively large, without abcauline caecum, 

about 20 tentacles, internal epidermal covering 

of hydrotheca often with thick patch of 

larger nematocysts near curvature of abcauline 

side. 

Gonothecae absent in examined material of 

branched colonies, in unbranched colonies on 

stem and stolons, ovoid, length 1 mm, width 0.7 

mm, walls undulated or smooth, this even in 

same gonotheca, end truncated, aperture wide 

and on short neck, on inside of neck a circle of 

small perisarc pegs. 

Variation 

Fertile colonies can also be composed of simple 

stems without hydrocladia. According to Billard 

(1925b) and Millard (1975), such simple stems 

can co-occur with pinnate ones. The simple 

stems are identical to hydrocladia of the branched 

form, including the oblique hinge joint. 

Remarks 

Dynamena moluccana Pictet, 1890 is here regarded 

as valid and distinct from D. cornicina, a 

view already expressed by Calder (1991). Billard 

(1925b) re-examined the type material of D. 

moluccana and synonymized it with Dynamena 

cornicina McCrady, 1859. Billard also referred


unbranched material identified by Pictet as S. 

compressa to D. cornicina. However, Calder 

(1991) showed that D. cornicina is not unambiguously 

identifiable and McCrady’s material 

could have been either Dynamena disticha 

(Bosc, 1802) or Sertularia distans (Lamouroux, 

1816) (syn. Dynamena distans Lamouroux, 1816 

or Tridentata distans; see Calder 1991). Calder 

(1991), Migotto (1996), Medel & Vervoort 

(1998) and others subsequently regarded D. cornicina 

as conspecific with Dynamena disticha 

(Bosc, 1802), a view also shared by the present 

author. However, comparison of Mediterranean 

material of Dynamena disticha (Fig. 30) with 

Dynamena moluccana (Fig. 29) revealed that 

both species are distinguishable. The shoots of 

Dynamena disticha (see Calder 1991 for description 

and synonyms) are usually simple (unbranched). 

Only rarely, some shoots can be 

branched once, as was found in material from the 

Mediterranean (Fig. 30A). This contrasts with D. 

moluccana, which is often pinnately branched, 

but colonies with unbranched stems also occur. 

Comparing the stems of both branched forms, it 

is evident that they are different. The stem of 

branched D. disticha has opposite hydrothecae 

and it does not differ in structure from the one of 

the side-branches (Fig. 30A). In D. moluccana, 

the stem differs profoundly from the hydrocladia: 

there are three hydrothecae per segment, 

the distal pair is subopposite to almost alternate, 

and the most proximal hydrotheca is almost completely 

free and strongly recurved (Fig. 29A). 

This structure of the stem segments has repeatedly 

been observed in material coming from 

different localities (e.g., Thornely 1904 (as Desmoscyphus 

palkensis); Billard 1925b, Vervoort 

1941, Cooke 1975, Millard 1975, Gibbons & 

Ryland 1989 (all as D. cornicina); Hirohito 1995 

(as D. exigua)). The hydrocladia of D. moluccana 

and D. disticha resemble each other very 

closely and it is understandable that both have 

been synonymized. It seems, however, that D. 

moluccana has slightly larger hydrothecae (abcauline 

side 0.40–0.45 mm versus 0.25–0.35 

mm). The gonothecae are also slightly different. 

Those of D. moluccana are more elongate, those 

of D. disticha characteristically spherical. The 

gonothecae of D. disticha are also often strongly 

annulated, sometimes even provided with trans- 

173 

Fig. 30. Dynamena disticha (Bosc, 1802); Mediterranean 

material. A. Stem with rare branching point. B. Gonotheca. – 

Scales: A–B = 0.2 mm. 

verse ribs, while the ones of D. moluccana are 

smooth, moderately annulated, or with transverse 

ribs (Cooke 1975, Millard 1975). The variability 

of the annulation precludes somewhat that 

this character can serve as a reliable diagnostic 

trait. The best characters to positively identify D. 

mollucana are thus the pinnate shoots and the 

stem morphology. Unbranched colonies of this 

species are difficult to separate from unbranched 

D. disticha, but a more oblong and smoother 

gonotheca as well as larger hydrothecae are characteristic 

for D. mollucana. Using these characters 

to distinguish the species, it is evident that 

Hirohito (1995) probably found both species in 

sympatry. Hirohito’s D. exigua is clearly recognizable 

as D. moluccana, while his D. cornicina 

is obviously referable to D. disticha. This sympatric 

occurrence of both morphotypes strongly 

argues in favour of two separate species being 

present and not geographic variants only (subspecies). 

It was noted that in the branched shoots of D. 

moluccana there is often a patch of larger nematocysts 

in the epidermal lining of the hydrotheca. 

This thickened patch, frequently found in many 

Sertulariidae (Schuchert 2001), is usually found 

at the curvature of the abcauline side of the

174 

hydrotheca. No such patches were found in D. 

disticha. However, not enough well preserved 

material could be examined to substantiate this 

difference. 

Both D. moluccana and D. disticha have a 

very thin and delicate hydrothecal perisarc. It is 

often damaged or distorted in preserved samples. 

Together with the frequent renovations they can 

look deceptively like hydrothecae of the genus 

Salacia. A careful search for undamaged hydrothecae 

will, however, reveal the difference (cf. 

Medel & Vervoort 1998: 31 and Cornelius 1979: 

309, note 21). The flimsy perisarc is actually an 

important trait to distinguish D. disticha from D. 

pumila. A further difference is the separation of 

the hydrothecae: they are not contiguous on either 

side. Dynamena pumila also forms branched 

and unbranched forms (see Cornelius 1995b 

or Schuchert 2001 for recent descriptions). 

Dynamena pumila occurs in cooler waters of the 

North Atlantic, while D. disticha is predominantly 

known from warmer water. 

The material identified by Pictet (1893) as 

Sertularia gracilis Hassal, 1848 (MHNG INVE 

25032) is clearly a Dynamena species and resembles 

somewhat D. moluccana, although it has 

simple shoots. But the hydrothecae are distinctly 

smaller (0.2 mm abcauline side) and they are on 

long internodes. It could thus belong to Dynamena 

dalmasi (Versluys, 1899) (see Calder 1991 

and Medel & Vervoort 1998 for recent descriptions). 

Distribution 

Indonesia (Pictet 1893, Billard 1925b), Papua 

New Guinea (Thornely 1904), Marshall Islands 

(Cooke 1975), Australia (Bale 1884, as S. divergens), 

Seychelles (Jarvis 1922 as S. cornicina 

var. pinnata), southern Africa (Millard 1975), 

Japan (Hirohito 1995, as D. exigua). Type locality: 

Bay of Ambon. 

Geminella ceramensis (Billard, 1925) 

Fig. 31. 

Sertularella ceramensis Billard, 1925a: 649. – Billard 

1925b: 170, fig. 30, pl. 7: fig. 20. 

Geminella ceramensis. – Vervoort 1993: 109, fig. 3a–e. 

Not Geminella ceramensis. – Vannucci Mendes 1946: 570, 

pl. 4: figs 40–41. 

P. SCHUCHERT 

Fig. 31. Geminella ceramensis (Billard, 1925). A. Pair of 

hydrothecae. B. Hydrothecal opening in oblique view showing 

the three opercular valves. C. Gonotheca. – Scales: A–B 

= 0.1 mm; C = 0.2 mm. 



Description 

Colonies erect, stems irregularly branched, up to 

1 cm in height. Stolons tubular, ramified. Stem 

and branches with identical structure, regularly 

segmented by more or less distinct transverse 

nodes. Segments elongate, 0.7–1.1 mm long, 

each with a pair of opposite to subopposite hydrothecae 

in its middle. Side-branches originate 

below a hydrotheca, first segment without hydrotheca, 

about half as long as other segments. 

Hydrotheca conical, adcauline side adnate 

for half or less of length, abcauline side almost


straight, 0.20–0.24 mm long; adcauline side bent 

where becoming free, free adcauline side straight 

to somewhat convex, opening-plane directed 

slightly upwards to nearly parallel to segment 

axis, diameter 0.13–0.15 mm, margin with three 

distinct cusps: one on adcauline side, two on 

lateral sides somewhat below middle; operculum 

pyramidal and composed of three valves; hydrothecal 

margin often renovated. Hydranths with 

abcauline caecum and about 12 tentacles. 

Gonothecae develop immediately below a hydrotheca. 

Gonotheca vase-shaped, 1.2 mm long, 

max. diameter 0.5 mm, base rounded and with 

short pedicel, sides quite straight and converging 

towards distal end; end truncated, walls with 15– 

18 distinct and sharp transverse ridges, some 

gonothecae with less distinct ridges and rather 

undulated only. 

Remarks 

Most gonothecae observed in this study had rather 

sharp transverse folds, and were not undulated 

as described by Vervoort (1993). 

Geminella ceramensis is the only known species 

of its genus. Geminella differs from the 

genus Symplectoscyphus only by its opposite 

hydrothecae, but Vervoort (1993) noted that initial 

stages of Geminella ceramensis have alternate 

hydrothecae. A future revision might thus 

synonymize Geminella and Symplectoscyphus. 

Distribution 

Indonesia, Philippines, New Caledonia. Type 

locality: Ceram, Banda Islands, 2.475°S, 

131.055°E, 118 m, on coarse sand. 

Idiellana pristis (Lamouroux, 1816) 

Fig. 32. 

Idia pristis Lamouroux, 1816: 199, pl. 5: fig. 5. – Allman 

1888: 85, pl. 39: figs 1–10. – von Campenhausen 1896b: 

311. – Billard 1925b: 219, fig. 58, pl. 7: fig. 33. – 


Pasythea philippina Marktanner-Turneretscher, 1890: 234, 

pl. 4: figs 8 & 8a. 

Idiella pristis. – Stechow & Müller 1923: 469. – Vervoort 

1959: 252. 

Idiellana pristis. – Ralph 1961a: 766, fig. 5c–e. – Mammen 

1965: 52, fig. 86. – Millard 1975: 269, fig. 88A–E. – 

Hirohito 1995: 178, fig. 58a–c. – Vervoort 1993: 188. – 

Migotto 1996: 64, fig. 12f–g. – Watson 2000: 18, fig. 

14A–E. 

175 

Figure 32. Idiellana pristis (Lamouroux, 1816); A, station 

71; B–C, station 66; D, station 53. A. Colony silhouette. B. 

Hydrocladium seen from anterior side. C. Hydrocladium in 

side view. D. Gonotheca, scale bar 0.5 mm. – Scales: A = 2 

cm; B, C = 0.4 mm; D = 0.5 mm. 


Kei Islands Expedition, Bay of Ambon, 13 m, 28 Feb 1922, 

sand bottom, fertile. – Kei Islands Expedition, Bay of 

Ambon, 90 m, 21 Feb 1922, bottom of stones and sand, 

fertile. – Kei Islands Expedition, Ujungpandang, Samalon 

Island, 25 m, 29 Jun 1922, sand bottom. – Kei Islands 

Expedition, Ujungpandang, Samalon Island, 35 m, 28 Jun 

1922, sand bottom. – Kei Islands Expedition, Ambon, harbour 

pier, 13 m, 27 Feb 1922, sand bottom. – Kei Islands 

Expedition stations: 11. – 14. – 19, fertile. – 20, fertile. – 21. 

– 36. – 40. – 53, fertile. – 57. – 61. – 64. – 65. – 66. – 67, 

fertile. – 68. – 69. – 71, fertile. – 72, fertile. – 73. – 74. – 90. 

– 103. – 104, fertile. – 106, fertile. – 107. – 110. – 117. – 118, 

fertile. 

Description 

Colonies pinnate, up to 7 cm high. Main stem 

unforked, monosiphonic, with regular nodes, 

nodes alternate in inclination, each segment with 

three non-contiguous hydrothecae and an apophysis 

near lower end. 

Hydrocladia alternate, widely spaced, un-

176 

branched, unsegmented or only few nodes 

present, bearing a double row of alternate, overlapping 

hydrothecae on the frontal face, the two 

rows contiguous with one another. 

Hydrotheca tubular, basal half parallel to hydrocladium, 

distal half curving away, length of 

abcauline side 0.6 mm, no internal teeth, rim with 

two indistinct lateral teeth, operculum composed 

of an adcauline flap, the base of which is not 

distinctly demarcated from hydrotheca, margin 

of hydrotheca often renovated and elongated like 

duck-bill. 

Gonothecae on stem, urn-shaped, 1.6 mm 

long, diameter 0.8 mm, with 8–10 longitudinal 

ridges, these partly serrated, distal aperture on 

conical collar. 

Remarks 

The alternate hydrothecae on the anterior surface 

of the hydrocladia, as well as the characteristic 

hydrothecae, make this species easy to identify. 

However, it is arguable why this species should 

be placed in a separate genus Idiellana and not in 

the genus Diphasia. The only difference between 

the two genera is the alternate arrangement of 

the hydrothecae in Idiellana. Hydrothecae on 

one side of the hydrocladium are also frequently 

found in Diphasia species. 

Distribution 

Widely distributed in tropical and subtropical 

regions of the world. Type locality: Australasia 

(as New Holland in Lamouroux, 1816). 

Salacia hexodon (Busk, 1852) 

Fig. 33. 

Pasythea hexodon Busk, 1852: 395. – Bale 1884: 113, pl. 9: 

fig. 13. – Bale 1888: 771, pl. 14: figs 8–9. – von Campenhausen 

1896b: 311. – Watson 2000: 21, fig. 16A–B. 

Salacia hexodon. – Billard 1925b: 207, fig. 49C–D. 


Kei Islands Expedition stations: 15. – 18. – 20. – 60. – 61. – 

67. – 68. – 71, with gonothecae. – 72, with gonothecae. – 90. 

– 107. 

Description 

Colonies erect, simple or irregularly branched, 

0.5–2 cm high, monosiphonic, with regular 

P. SCHUCHERT 

Fig. 33. Salacia hexodon (Busk, 1852); station 71. Part 

of shoot showing typically clustered hydrothecae, a sidebranch, 

and a gonotheca. – Scale: 0.5 mm. 

transverse nodes above groups of hydrothecae. 

Hydrothecae on lateral sides, clustered in groups 

of 5–7 (range 2–10, reportedly also more), within 

these clusters consecutive individuals of one row 

in contact, the two rows not contiguous, long, 

tubular regions between the groups of hydrothecae. 

Branching points of side-branches below 

a hydrotheca. 

Hydrotheca tubular, abcauline side 0.4 mm, 

curved, adnate for half of its adcauline length, 

opening circular, angle variable, opening-plane 

parallel to stem or inclined towards below, with 

single operculum attached to abcauline side. Hydranth 

without abcauline caecum, one abcauline 

tentacle longer than others, thick club-shaped 

with larger nematocysts than in other tentacles. 

Gonothecae arising below lowest hydrotheca


of a cluster, urn-shaped, 1.4 mm long, diameter 1 

mm, with 8–10 transverse ridges or ribs. 

Distribution 

Australia, Indonesia. Type locality: Whitsunday 

Islands, Queensland, Australia (as Cumberland 

Islands in Busk, 1852). 

Salacia sibogae Billard, 1924 

Fig. 34. 

Salacia sibogae Billard, 1924: 64, fig. 1B–C. – Billard 

177 

1925b: 206, fig. 49, pl. 8: fig. 30. – Hirohito 1995: 185, 

fig. 60f. 


Kei Islands Expedition stations: 3. – 12, with gonothecae. – 

14, with gonothecae. – 58. 

Description 

Colonies erect, pinnate. Stem 5–12 cm, monosiphonic, 

unbranched, zigzag, thicker than hydrocladia, 

regularly segmented by transverse to 

slightly oblique nodes, nodes flanked by bulges 

of the segment ends. Each stem segment with 

Fig. 34. Salacia sibogae Billard, 1924; A, station 12; B–E, station 14. A. Colony silhouette. B. Stem segment with base of 

hydrocladium. C. Segment from hydrocladium, note faint lateral crease lines originating from hydrothecal margin. D. Oblique 

view of hydrotheca, note possible upper opercular valve (dotted). E. Gonothecae in oblique view. F. Distal part of gonotheca 

in side view, shown transparent, same scale as E. – Scales: A = 1 cm; B, E = 0.5 mm; C, D = 0.2 mm.

178 

three alternate hydrothecae in two lateral rows 

and a long apophysis below the distal-most hydrotheca. 

Hydrocladia alternate, straight, with up to 10 

segments, nodes transverse and distinct, flanked 

by swellings of the segment ends, segments long 

and thin, quite uniform in length (1.5–1.6 mm). 

Hydrocladial hydrothecae in two lateral rows, in 

strictly opposite pairs in the distal half of the 

segment, members of a pair not contiguous on 

any side, consecutive hydrothecae of one row 

very far apart. 

Hydrotheca curved, free part wedge-shaped 

in lateral view, duck-billed in oblique view, adcauline 

side adnate for less than half its length, 

sharply bent where becoming free, adnate part 

0.4 mm long, free adcauline side nearly horizontal, 

straight to slightly concave, 0.55–0.60 mm 

long, upper side of hydrotheca shaped like a 

gabled roof, with lateral crease lines. Periderm of 

distal part of hydrotheca very thin and flexible. 

Opening very oblique, with one large, oval adcauline 

opercular flap, sometimes repeatedly 

present; perhaps also a small, very indistinct adcauline 

opercular valve present. Hydranth with 

about 20 tentacles, without abcauline caecum. 

Gonothecae on stem, often opposite a hydrocladium. 

Gonotheca oblong, about 2 mm long, maximal 

diameter about 1 mm, distal end truncate, 

opening on a short neck with wide diameter, 

lateral wall of gonotheca with about 6 thick 

annulations; near distal end an interior ring of 

periderm knobs. 

Remarks 

With its relatively large, pinnate colonies, and 

especially the widely spaced hydrothecal pairs 

with their long wedge-shaped ends, Salacia sibogae 

is quite easily identifiable in the present 

fauna. All examined samples come from a small 

area north-east of the Kei Island archipelago, not 

far from the type locality of the species. Most 

records lie in deeper waters, with a range of 40– 

450 m (of the seven known records six are below 

245 m, only one is from 40 m). 

Although the identity of the present material 

with Billard’s species is quite certain, the allocation 

of this species to the genus Salacia is not 

P. SCHUCHERT 

entirely secure because there might be more than 

just one opercular valve and the species appears 

intermediate between the genera Dynamena and 

Salacia. In many hydrothecae, the adcauline (upper) 

margin is thinner and it looks like a short 

adcauline opercular valve partitioned by a short 

median tooth (Fig. 34D). This was only visible in 

the stereomicroscope and the putative valve is 

not distinctly demarcated at its base. It was not 

possible to evaluate whether this is a true, rudimentary 

operculum or only an illusion. However, 

the hydrotheca is not entirely typical for the 

genus Salacia and perhaps the genus Dynamena 

might be more appropriate for this species. Millard 

(1975) mentions that in Dynamena the upper 

valve is usually smaller and it may have a median 

partition (see Dynamena crisioides). However, 

the distal part of the hydrotheca of S. sibogae is so 

flimsy and difficult to observe that no clear answer 

seems possible with ordinary light microscopy. 

Distribution 

Indonesia, Indian Ocean (Hirohito 1995). Type 

locality: Kei Islands, 5.473°S, 132.000°E, 204 m, 

on hard coralline sand. 

Salacia punctagonangia (Hargitt, 1924) 

Fig. 35. 

Sertularia punctagonangia Hargitt, 1924: 469, pl. 6: fig. 23. 

?Salacia spec. – Hirohito 1995: 185, fig. 60d–e. 


Sertularia punctagonangia, NMNH, slide reg. number 

USNM 42655, part of a plume with male gonothecae. 


Kei Islands Expedition station 4, with female gonothecae. 


Similar to Salacia sibogae Billard, 1924 (see 

above), but stem occasionally forked, 7 cm high, 

nodes on stem absent in proximal region. Hydrocladial 

hydrothecae smaller, subopposite, some 

almost alternate, few opposite. Free adcauline 

wall of hydrotheca convex in side view, crosssection 

rounded and not roof-shaped, without 

lateral crease lines. Gonotheca smooth-walled, 

oblong oval, tapering below into pedicel, termi-


Fig. 35. Salacia punctagonangia (Hargitt, 1924); station 4. A. Colony silhouette. B. Part of stem and hydrocladia. C. Side view 

of typical pair of hydrothecae. D. Oblique view of hydrothecal opening. E. Gonotheca in side view. – Scales: A = 1 cm; B, E 

= 0.5 mm; C = 0.2 mm. 

nal end truncate, with large convex operculum, 

with slight sub-terminal constriction, at height of 

constriction a ring of internal wart-like periderm 

nodules. Measurements: length of free adcauline 

wall of hydrotheca 0.4–0.5 mm, adnate part 0.3 

mm, length of female gonotheca 1.8 mm, male 

gonotheca 1.3–1.4 mm. 

Remarks 

Salacia punctagonangia (Hargitt, 1924) is a rare 

species, so far only recorded from the Philippines 

(Hargitt 1924). Re-examination of Hargitt’s material 

showed that the present Indonesian material 

is indistinguishable from it. The only notable 

difference is the size of the gonothecae, the 

length of which is 1.3–1.4 mm in the type mate- 

179 

rial, but 1.8 mm in the material from the Kei 

Islands. The type material is clearly male, while 

the Indonesian material contains oocytes. The 

size difference is thus likely to be explained by 

the different sexes. 

Salacia punctagonangia (Hargitt, 1924) so 

closely resembles Salacia sibogae Billard, 1924, 

especially in the aspect of the colony, hydrothecae 

and dimensions, that I took it first as a 

variant of the latter. However, the various small 

differences are convincing evidence that the two 

morphotypes belong to different species. Both 

morphotypes were fortunately found at localities 

so close together (less than one nautical mile 

apart), that the respective populations must be 

considered sympatric. Because both localities are 

in rather deep waters (245 and 250 m) where

180 

environmental conditions can be assumed to be 

virtually identical, the morphological differences 

do certainly reflect genetic differences and not 

phenotypic variations. These presumably genetic 

differences of sympatric specimens were considered 

due to two different species being involved. 

At closer examination, both species are reliably 

distinguishable using the differences given in the 

diagnosis above. The most important characters 

to distinguish S. punctogonagia from S. sibogae 

are the subopposite hydrothecae, the curved convex 

free adcauline wall of the hydrotheca, and the 

smooth gonotheca. 

As for S. sibogae, the hydrothecal margin in 

this species is also very thin and flimsy and it is 

not entirely clear whether the species belongs to 

Salacia or Dynamena. 

Salacia punctagonangia is here recorded for 

the first time for Indonesia. It was previously 

only known from the Philippines. Hirohito 

(1995, as Salacia sp.) compares a Salacia species 

from Sagami Bay (Japan) with Salacia sibogae 

from the Indian Ocean. This Japanese material, 

although infertile, shows all characteristics of S. 

punctagonagia and is likely to belong to this 

species. 

Distribution 

Philippines, Indonesia, ? Japan. Depths: 120– 

400 m. Type locality: Batan, Philippines, 120– 

274 m. 

Salacia sinuosa (Bale, 1888) 

Fig. 36. 

Thuiaria sinuosa Bale, 1888: 772, pl. 18: figs 9–10. – 

Ritchie 1911: 844, pl. 85: fig. 4. 

Salacia sinuosa. – Billard 1925b: 204, fig. 48, pl. 8: fig. 29. 

– Watson 2000: 22, fig. 17E. 


Kei Islands Expedition station 74, without gonothecae. 

Description 

Colony large, bush-like, up to 25 cm high, much 

branched, trunk at base up to 3 mm thick and 

woody, strongly polysiphonic through overgrowth 

of stolon-like tubes, only distal-most tips 

monosiphonic, ultimate branches pinnate, pinnate 

parts up to 5 cm long, stem of pinnate 

P. SCHUCHERT 

Fig 36. Salacia sinuosa (Bale, 1888). A. Teminal part of 

branch with base of hydrocladium B. Part of hydrocladium 

seen from broad side. – Scales: A = 0.5 mm; B = 0.2 mm. 

regions also polysiphonic. Stolons forming a 

root-like structure which anchors colony in sediment. 

Monosiphonic distal ends of stem with 

transverse nodes, segments short, each with three 

hydrothecae and an apophysis, a single hydrotheca 

opposite apophysis, two on side of apophysis. 

Hydrothecae of stem in two lateral rows, 

alternate, not in contact vertically or horizontally. 

Apophysis inserted between two successive hydrothecae 

of a segment, node to hydrocladium 

twisted. 

Hydrocladia stiff, straight, flattened, only occasionally 

a node present, with two lateral rows 

of overlapping hydrothecae. Hydrothecae of one 

row adjacent, oblique, overlapping for about 1/3


of length. Hydrothecae of the two rows not in 

contact, in opposite to subopposite pairs. 

Hydrotheca tubular, narrowing from base to 

margin; adcauline wall 0.47–0.50 mm, almost 

completely adnate, only a very short upper rim 

free; lower half of abcauline side adnate to previous 

hydrotheca, free abcauline side mostly 

straight, nearly parallel to hydrocladium axis, 

0.18–0.20 mm long, below margin a perisarc 

thickening and sometimes with a short inward 

fold; opening in frontal view ovate, openingplane 

parallel to hydrocladial axis or somewhat 

tilted towards below. Operculum a single valve 

attached to abcauline margin of hydrotheca, often 

several ones present. Below the side of some 

hydrothecae a round fenestration. 

Gonothecae not observed, according to Watson 

(2000) oblong, up to 1.5 mm long, width up 

to 0.54 mm, inserted between the rows of hydrothecae, 

wall smooth or with faint annulations, 

aperture on short neck at distal end. Colour 

of preserved material: stem dark brown, upper 

branches and hydrocladia light brown. 

Distribution 

Subtropical Australia, Indonesia. Type locality: 

Port Molle, Australia. 

Salacia tetracythara Lamouroux, 1816 

Fig. 37. 

Salacia tetracythara Lamouroux, 1816: 212: pl. 6: fig. 3a–c. 

– Billard 1925b: 202, fig. 47, pl. 3: figs 27–28. – 

Mammen 1965: 54, fig. 87. – Rees & Vervoort 1987: 

103, fig. 6d. – Gibbons & Ryland 1989: 414, fig. 31. – 

Hirohito 1995: 183, fig. 60a–c. – Watson 2000: 23, fig. 

18A-F. 

Thuiaria fenestra Bale, 1884: 116, pl. 7: fig. 7, pl. 9: fig. 14. 

Calyptothuiaria opposita von Campenhausen, 1896b: 312, 

fig. 7. 


Kei Islands Expedition stations: 69. – 71. – 72, with gonothecae. 

– 91. – 104, with gonothecae. – 106. – 107. 

Description 

Colonies erect, pinnate, up to 6 cm in present 

material (reportedly up to 10 cm), sometimes 

neighbouring shoots connected through 

distal tendrils of hydrocladia. Stems mostly unbranched, 

monosiphonic or polysiphonic, peri- 

181 

Fig. 37. Salacia tetracythara Lamouroux, 1816; station 72. 

A. Part of stem and base of hydrocladium. B. Hydrocladium 

in side view and attached gonotheca. – Scale: A–B = 0.2 mm. 

sarc thick, nodes only visible in distal regions, 

two lateral rows of hydrothecae, these not in 

contact, in subopposite pairs, three between 

successive hydrocladia of one side, apophyses 

for hydrocladia short, mostly delimited by node 

from hydrocladium. 

Hydrocladia in one plane, alternating, 

straight, stiff, length variable, held at approximately 

60°–80° to stem, occasionally branching 

2–3 three times, with numerous hydrothecae, 

nodes rare, distal end occasionally transformed 

into stolon-like tendril. Hydrothecae in two lateral 

rows, in opposite to subopposite pairs, members 

of a pair not in contact, successive hydrothecae 

of a row in contact and overlapping. 

Hydrotheca tubular, adnate for 9/10 of their 

adcauline length, proximal half to 2/3 of adcauline 

side straight, remaining part curved so 

that opening slightly tilted downward, abcauline 

side straight for nearly its entire length, length

182 

about 0.3 mm. Hydrothecal opening in frontal 

view elliptical, margin with three shallow teeth: 

two lateral ones and one median adcauline, opcerculum 

one oval valve attached on abcauline 

side of hydrothecal rim, often repeated. Hydranth 

without abcauline caecum, with about 20 tentacles. 

Gonothecae on stem and hydrocladia, all on 

one side, held perpendicular to plane of ramification. 

Gonothecae globular to urn-shaped, length 

1 mm, diameter in middle 0.75 mm, aperture 

wide, 0.5 mm diameter, on short neck, operculum 

convex, on inside of neck a ring of perisarc 

projections. 

Distribution 

Vietnam, Indonesia, Australia, India, Japan. 

Type locality: Australia. 

P. SCHUCHERT 

Caminothujaria molukkana 

von Campenhausen, 1896 

Fig. 38. 

Caminothujaria molukkana von Campenhausen, 1896a: 

104. – Vervoort 1993: 102, synonymy. 

Caminothujaria moluccana. – von Campenhausen 1896b: 

306, pl. 15: fig. 8. 

Thuiaria divergens Whitelegge, 1899: 372, pl. 22, figs 1–3. 

– Billard 1925b: 222. 

Sertularia indomalayica Stechow, 1919: 158. 

Sertularella singularis Billard, 1920a: 14, fig. 1. 

Sertularia sigmagonangia Hargitt, 1924: 495, pl. 5: fig. 20. 

Sertularella moluccana. – Billard 1925b: 167, figs 28–29, 

pl. 7: fig. 19. 

Dictyocladium aberrans Nutting, 1927: 214, pl. 41: figs 4–5. 


Kei Islands Expedition stations: 21. – 26. – 27. – 53. – 54, 

with gonothecae. – 68. – 103. 

Description 

Colonies erect, pinnate, up to 7 cm high. Stolons 

Fig. 38. Caminothujaria molukkana von Campenhausen, 1896; A, station 53; B–E, station 26. A. Colony silhouette. B. Part 

of stem and base of hydrocladium. C. Paired hydrothecae. D. Verticil with four hydrothecae, opercular valves drawn dotted. 

E. Gonotheca in side view, same scale as B. – Scales: A = 1 cm; B, E = 0.5 mm; C = 0.2 mm; D = 0.4 mm.


root-like or creeping. Stems unforked, monosiphonic 

in younger colonies, older colonies polysiphonic 

in lower half; with alternate hydrocladia 

which are more or less in one plane, nodes 

along stem absent or very indistinct. Hydrothecae 

of stem in two lateral rows, in groups of three 

close to origins of hydrocladia, one hydrotheca 

opposite hydrocladium, one axillary, one below 

hydrocladium; end of adcauline wall of stem 

hydrothecae often with process. 

Hydrocladia alternate, straight, occasionally 

branched secondarily, held at right angle to stem, 

can be long but length variable, with up to 24 

hydrothecal pairs or verticils, nodes rare. Hydrothecae 

of hydrocladia either in opposite pairs 

(rarely subopposite), or in verticils of three or 

four; paired hydrothecae in plane of colony. Verticils 

with 3–4 hydrothecae more frequent near 

proximal end of hydrocladium, more distal hydrothecae 

usually in pairs. 

Hydrotheca uniform, curved so that openingplane 

is nearly parallel to hydrocladium or somewhat 

inclined towards above, adcauline wall adnate 

for half its length or less, abcauline wall 

about 0.45 mm long, diameter of opening 0.22 

mm; rim with four low but acute cusps (two 

laterals, one adcauline, one abcauline); operculum 

composed of four valves, pyramid-like; 

renovations of margin frequent, lower end of 

adcauline wall often with swelling, this swelling 

variably present, sometimes this swelling extended 

like an annular thickening. Hydranths 

with abcauline caecum. 

Gonothecae on hydrocladia, long axis parallel 

to hydrocladium, shape elongate-fusiform and 

slightly S-curved, about 2 mm long, maximal 

diameter 0.6 mm; body with 6–8 sharp transverse 

crests; opening terminal, rather small, surrounded 

by three distinct cusps, one adcauline, 

two laterals; opening covered by operculum divided 

into four flaps. 

Remarks 

With its four-cusped hydrothecae in either opposite 

pairs or verticils of three or four, this species 

is easily recognizable. Juvenile colonies may 

have only paired hydrothecae. 

183 

Distribution 

Indonesia, Philippines, Ellis Islands. Type locality: 

Ternate, Moluccas, Indonesia. 

Sertularella decipiens Billard, 1919 

Fig. 39. 

Sertularella decipiens Billard, 1919b: 21, fig. 3B. – Billard 

1925b: 155, fig. 21, pl. 7: fig. 15, pl. 8: fig. 34. – Watson 

2000: 27, fig. 22A–E. 



Fig. 39. Sertularella decipiens Billard, 1919. A. Stem internode 

with base of hydrocladium. B. Part of hydrocladium. C. 

Gonotheca, same scale as A. – Scales: A, C = 0.5 mm; B = 0.2 

mm

184 

Description 

Colonies erect, pinnate, up to 3 cm high, stems 

unbranched, monosiphonic, basal part without 

hydrothecae, delimited by oblique node from 

distal part; distal part with alternate hydrocladia 

and hydrothecae in two lateral rows, nodes at 

least in more distal parts visible, internodes elongate, 

apophysis for hydrocladium arising below 

most distal hydrotheca of internode, apophysis 

rather short, delimited by node from hydrocladium. 

Hydrocladia quite long, some with one or two 

side-branches, with distant nodes and a variable 

number of hydrothecae per internode. The two 

rows of hydrothecae on stem and hydrocladia 

more or less in one plane. Hydrothecae alternate, 

successive hydrothecae of one row well separated 

by a gap of about half a hydrothecal length. 

Hydrotheca roughly tubular, adnate for 7/8 

of length, adcauline side curved, abcauline wall 

straight for almost entire length and nearly parallel 

to hydrocladial axis, length of abcauline wall 

around 0.45 mm, diameter of opening 0.2 mm, 

opening-plane almost parallel to hydrocladial 

axis, margin with four pointed cusps, slightly 

below margin of abcauline side at point of flexure 

a short intrathecal shelf. Floor of hydrotheca not 

reaching abcauline side, without distinct process 

towards interior of internode. 

Gonothecae developing in small clusters at 

very base of stem near junction to stolons. Gonotheca 

very large, length 3 mm without pedicel, 

major part cylindrical, tapering and curving below 

into pedicel, distal part with spiral annulation 

grading into shallow annulation and smooth part 

below, distal end truncate, margin with four shallow 

cusps, operculum pyramidal, composed of 

four flaps. 

Remarks 

Stechow & Müller (1923) doubted the validity of 

this species, suggesting it may be conspecific 

with S. quadridens. This was contested by Watson 

(2000) who described the gonotheca for the 

first time. The gonothecae of S. decipiens are 

larger and curved, have a spiral annulation, and 

develop at the base of the stem. The gonothecae 

of S. quadridens are smaller (up to 2.2 mm), 

straight, with sharp transverse ridges, and they 

P. SCHUCHERT 

develop in the hydrocladiate region of the stem. 

The examined samples of S. decipiens agreed 

well with Billard’s (1925b) description, which 

was also based on material from the Kei Islands. 

The Indonesian material shows some minor differences 

to the material of northern Australia 

described by Watson (2000): the hydrothecae are 

notably more widely spaced, the hydrocladia are 

sometimes branched, and the lower part of the 

gonotheca is smooth. These differences are here 

interpreted as intraspecific variation. The characteristic 

site of gonotheca development at the base 

of the stem renders this species quite easily identifiable. 

Distribution 

Indonesia, northern Australia. Type locality: 

Tual, Kei Islands, Indonesia, 22 m. 

Sertularella diaphana (Allman, 1886) 

Fig. 40. 

Thuiaria diaphana Allman, 1886: 145, pl. 18: figs 1–3. 

Sertularella diaphana var. delicata Billard, 1919b: 21, fig. 

3A. – Billard 1925b: 161, fig. 24, pl. 7: fig. 14. 

Sertularella diaphana var. orthogona Billard 1925b: 161, 

fig. 23. 

Sertularella diaphana var. gigantea Billard, 1925b: 161, pl. 

9: fig. 35. – Vervoort 1941: 213. 

Sertularella diaphana. – Bale 1919: 337, pl. 16: fig. 5. – 

Billard 1925b: 157, fig. 22 pl. 7: figs 12–13. – Millard 

1975: 285, fig. 93A–D. – Calder 1991: 101, fig. 53, 

synonymy. – Vervoort 1993: 214, figs 45d–e & 46d, 

synonymy. – Hirohito 1995: 192, fig. 62b–d, pl. 12: fig. 

A. – Watson 2000: 31, fig. 24, synonymy. 


Kei Islands Expedition station 107, on hydroid, with gonothecae. 

– Kei Islands Expedition, Neira Island, Banda 

Islands, 10 m, 5 Jun 1922, on hydroids, sponges and other 

substrata, numerous colonies, many with gonothecae. – Kei 

Islands Expedition, Bay of Ambon, 90 m, 2 Mar 1922, 

bottom of stones and sand, no gonothecae, corresponds to S. 

diaphana var. orthogona. 

Description 

Colonies erect, reaching heights of 12 cm, multipinnate. 

Stem thick, polysiphonic, forked or not, 

final branches pinnate with alternate hydrocladia 

which are more or less in one plane. Stem and 

branches divided into internodes in distal regions 

only, nodes oblique, sloping alternately to left 

and right. Each stem internode bearing three


Fig. 40. Sertularella diaphana (Allman, 1886); Neira Island. 

A. Colony silhouette, height about 6 cm. B. Stem internodes 

with bases of hydrocladia. C. Hydrothecae of hydrocladium. 

D. Gonotheca. – Scales: B = 0.5 mm; C = 0.2 mm. 

hydrothecae in two rows and one hydrocladium, 

the latter rising just below the most distal hydrotheca. 

Hydrocladium straight, unbranched, with distant 

nodes and a variable number of hydrothecae 

per internode. The two rows of hydrothecae on 

185 

stem, branches and hydrocladia shifted somewhat 

to anterior surface. Hydrothecae alternate, 

the two rows of hydrothecae on the hydrocladia 

either in one plane or in two planes of variable 

obtuse to right angle, both rows well separated. 

Hydrotheca completely adnate or very nearly 

so, without floor, smooth, curved outwards, 

opening tilted towards abcauline side, adcauline 

side about 0.5 mm, opening diameter 0.22–0.25 

mm. Marginal cusps low but pointed, no internal 

teeth. Lower end of adcauline hydrothecal wall 

often ending in a swelling, especially so in the 

cauline hydrothecae (Fig. 40B). 

Gonothecae borne on anterior surface of hydrocladia, 

elongated, polygonal in cross-section, 

truncated distally, length 2 mm, diameter 0.7 

mm, no marginal spines, 

Variation 

The variant Sertularella diaphana var. delicata 

forms 1 cm high, monosiphonic shoots; variant S. 

diaphana var. orthogona has the two rows of 

hydrothecae set at a right angle; variant gigantea 

forms very large colonies, reaching dimensions 

of 35 x 28 cm (all after Billard 1925b). 

Remarks 

Only an abbreviated synonymy of this species is 

given here because several authors provided one 

in recent publications (Calder 1991, Vervoort 

1993, Watson 2000). The sample from the Bay of 

Ambon was clearly referable to the variant orthogona, 

although it lacked the thickenings at the 

lower end of the adcauline hydrothecal wall. 

Vervoort (1993) also mentions material of this 

variant lacking the thickening. 

Distribution 

Widespread in tropical and subtropical waters 

of the Indo-Pacific and Atlantic. Type locality: 

Moreton Bay, Queensland, Australia. 

Sertularella quadridens (Bale, 1884) 

Fig. 41. 

Thuiaria quadridens Bale, 1884: 119, pl. 7: figs 5–6. – 

Weltner 1900: 586, pl. 46: figs 1–3. 

Thuiaria vincta Allman, 1888: 68, pl. 32: figs 2 & 2a. 

Sertularella quadridens. – Ritchie 1910b: 818, pl. 77: fig.

186 

12a–b. – Stechow & Müller 1923: 471. – Billard 1925b: 

150, fig. 19. – Vervoort 1941: 214, fig. 5. – Mammen 

1965: 38, fig. 70. – Watson 2000: 28, fig. 23. 

Sertularella timorensis Billard, 1919b: 21, fig. 1f–g. 

Sertularella polyzonias var. cornuta Ritchie, 1909: 525. – 

Ritchie 1910a: 10, pl. 4: fig. 2. 

P. SCHUCHERT 

Fig. 41. Sertularella quadridens (Bale, 1884); A–E, typical form, station 18; F–G, variant form “cornuta”, Samalon Island; H– 

I, variant form “timorensis”, station 26. A. Colony silhouette. B. Stem internode with base of hydrocladium. C–H. 

Hydrocladial hydrothecae, note variation of spacing and process at end of adcauline side, all drawn to same scale. I. Gonotheca, 

same scale as B. – Scales: A = 1 cm; B & I = 0.5 mm; C–H = 0.2 mm. 

Sertularella cornuta. – Stechow 1923: 12. – Nutting 1927: 

215, pl. 42: figs 1–2. 

Sertularella quadridens var. cornuta. – Billard 1925b: 151, 

pl. 7: fig. 9. – Vervoort 1941: 216. 

Sertularella quadridens var. timorensis. – Billard 1925b: 

153, fig. 20, pl. 7: figs 10–11.


Sertularella quadridens forma quadridens Ralph, 1961a: 

830, fig. 23h. 

Sertularella quadridens cornuta. – Vervoort 1993: 232, figs 

52b–e, 53a–b. 


Normal form 

Kei Islands Expedition station 18, several stems, no gonothecae. 

Morphotype “cornuta” 

Kei Islands Expedition stations: 16. – 60. – 63. – 64. – 103. 

– 104. – 106. – Kei Island Expedition, Samalon Island near 

Ujungpandang, 35 m, 28 Jun 1922. 

Morphotype “timorensis” 

Kei Islands Expedition station 26, one shoot with gonotheca, 

much overgrown by Bryozoa and algae. 

Description of typical form 

Colonies erect, pinnate, reaching heights of 7 cm. 

Stems monosiphonic, unbranched, with alternate 

hydrocladia which are more or less in one plane, 

divided into internodes in distal regions only, 

nodes oblique, sloping alternately to left and 

right. Each stem internode bearing three hydrothecae 

in two rows and one hydrocladium, the 

latter rising just below the most distal hydrotheca. 

Hydrocladia straight, unbranched, with distant 

nodes and a variable number of hydrothecae 

per internode. 

Hydrothecae alternate, the two rows of hydrothecae 

on the hydrocladia in one plane, both 

rows well separated, successive hydrothecae of 

one row well separated for about somewhat less 

than the length of one hydrotheca. Hydrotheca 

tubular, curved outwards, adnate for 2/3 to ¾ of 

its adcauline length, length of abcauline side 

0.30–0.35 mm, diameter of opening 0.20–0.23 

mm, length of free adcauline side 0.13–0.18 mm, 

adcauline side evenly curved, abcauline side 

straight in lower part and curved in last fourth, 

opening oblique, margin with four cusps; floor 

complete, with large pore, lower end of adcauline 

wall often with an oblique or vertical process, 

sometimes even connected to opposite hydrotheca 

(Fig. 41B), size and form of this process 

very variable within the same shoot (Fig. 41B– 

D), many hydrothecae even without such a process. 

Gonothecae of this form not observed (see 

Watson 2000, Billard 1925b). 

187 

Variant form “cornuta” 

Colony 2–5 cm high, hydrothecae slightly larger 

(abcauline wall 0.35–0.4 mm), hydrotheca more 

projecting (adnate for 2/3), process at lower end 

of adcauline wall absent or represented by a 

slight thickening only (Fig. 41E–G). No gonothecae 

present. 

Variant form “timorensis” 

Colony 3 cm high, perisarc much thickened, a 

large and massive intrathecal tooth on adcauline 

side, often also smaller on abcauline side, hydrothecae 

adnate for 2/3 to ¾ of their adcauline side, 

length abcauline side 0.38–0.40 mm, diameter of 

opening 0.15–0.16 mm. Gonotheca on hydrocladia, 

about 1.2 mm long, diameter 0.5 mm, 

barrel-shaped, with transverse annulation, end 

truncate, square, with four sharp corners, operculum 

pyramidal and composed of four triangular 

flaps. 

Remarks 

Typical Sertularella quadridens have hydrothecae 

with a characteristic process at the lower end 

of the adcauline wall (Fig. 41B–D), which renders 

them relatively easy to identify, even in the 

absence of the characteristic gonotheca. However, 

this process is very variable and can be 

absent in quite a number of hydrothecae. Therefore, 

also otherwise closely similar colonies lacking 

this process (variant forms) were here also 

allocated to this species. One of these variant 

forms likely corresponds to the form described 

by Billard (1925b) as S. quadridens var. cornuta. 

Billard (1925b) distinguished this variant from 

the typical form through the more widely spaced 

and more projecting hydrothecae and smaller 

gonotheca with longer marginal cusps. The status 

of this variant is at present unclear. Ritchie (1909, 

1910a) suggested it to be a variant of S. polyzonias, 

but Stechow (1923) and Nutting (1927) 

recognized it as a full species, an opinion also 

favoured by Watson (2000). Billard (1925b) and 

Vervoort (1941, 1993) regarded it as a variant of 

S. quadridens. Another variant is S. quadridens 

var. timorensis, a morphotype originally described 

as a separate species by Billard (1919b), 

but later demoted to a mere variant of S. qua-

188 

dridens by Billard (1925b) himself. This characteristic 

variant has a much thicker perisarc, 

massive intrathecal teeth, and smaller gonothecae 

than the normal form. Additionally, it 

seems to become mature at a smaller size. The 

thickenings at the lower end of the adcauline 

hydrothecal walls are somewhat masked by the 

general thickening of the perisarc. With the available 

material it was not possible to gain more 

insight into the status of these morphotypes. 

More fertile material of all three morphotypes, 

preferentially from the same locality and accompanied 

with detailed ecological information, 

must be examined and compared to re-assess 

their validity. 

Distribution 

Indonesia, Philippines, India, northern Australia, 

New Caledonia. Type locality: Pt. Curtis, 

Queensland, Australia. 

Sertularia loculosa Busk, 1852 

Fig. 42. 

Sertularia loculosa Busk, 1852: 393, pl. 19: fig. 9. – Migotto 

1996: 71, fig. 13f–i. 

Sertularia ligulata Thornely, 1904: 116, pl. 2: fig. 1–1B. – 

Billard 1925b: 178, fig. 35. – Millard 1958: 193, figs 

8C, 9A–B. – Vervoort 1959: 277, fig. 37. – Millard & 

Bouillon 1973: 74, fig. 9G. – Millard 1975: 307, fig. 

100A–D. – Vervoort & Vasseur 1977: 53, fig. 24. – 

Gibbons & Ryland 1989: 420. – Hirohito 1995: 213, fig. 

71a–g. 

Sertularia turbinata. – Ritchie, 1910b: 821. – Bale 1913: 

124, pl. 12: fig. 6. – Jäderholm 1919: 14, pl. 3: fig. 8. – 

Jarvis 1922: 341, pl. 19: fig. 8 (synonyms after Billard 

1925b). [Not Sertularia turbinata (Lamouroux, 1816)] 

Not Sertularia loculosa. – Bale 1884: 91. – Thornely 1904: 

118. – Warren 1908: 306. – Jarvis 1922: 340 [all S. 

turbinata]. 


Kei Islands Expedition stations: 67. – 90. – 106. 

Description 

Colonies forming erect, monosiphonic shoots, up 

to 3 cm high, usually unbranched but rarely 1–2 

short side-branches; basal ahydrothecate part 

ending in oblique hinge joint, distal part bearing 

hydrothecae in opposite pairs; nodes mostly absent 

or indistinct. Members of a pair of hydrothecae 

contiguous in front, separate on rear side. 

P. SCHUCHERT 

Fig. 42. Sertularia loculosa Busk, 1852; station 67. A. Two 

pairs of hydrotheca just above hinge joint. B. Hydrotheca 

with ligula (hydranth not shown), operculum shown with 

broken line. – Scales: A = 0.2 mm; B = 0.1 mm. 

Branches, when present, with structure identical 

to stem. 

Hydrotheca adnate for 2/3 of its adcauline 

length, height 0.3 mm, adcauline side bent at 90°, 

hydrotheca broadest somewhat above middle, 

opening-plane parallel to stem axis, margin with 

two very shallow lateral cusps or irregularly undulated, 

operculum composed of two valves, abcauline 

one large and circular, covering nearly 

the whole opening and often tucked into hydrotheca; 

abcauline valve very small, rudimentary, 

often not observable. On abcauline side 

somewhat below opening an oblique, semicircular 

ridge projecting into lumen of hydrotheca. On 

adcauline side of hydranth a long process with 

a terminal, swollen, finger-like region densely 

studded with large nematocysts (= ligula, nematophore). 

Hydranth with abcauline caecum. 

Gonotheca not observed, according to Migotto 

(1996) barrel-shaped, annulated, about 1 

mm long and 0.6 mm broad.


Remarks 

The characteristic ligula makes this species easily 

identifiable (Fig. 42B). The lateral cusps of 

the hydrothecal margin are very shallow and 

often difficult to observe. They are best seen 

under a stereomicroscope. The grossly unequal 

upper and lower valve of the operculum set this 

species somewhat apart from other Sertularia 

species. In this and the inconspicuous lateral 

marginal cusps, this species approaches the genus 

Thuiaria. However, the habitus resembles 

more that of Salacia, and only the presence of an 

abcauline caecum and the ligula may prevent 

misidentification. 

Some authors (e.g., Millard 1975) described 

this species as having an intrathecal septum. 

However, there is no true septum but merely a 

semicircular ridge projecting into the hydrothecal 

lumen (Fig. 42B). This ridge is moreover 

not transverse as shown in several figures, 

but slightly inclined towards the rear. Billard 

(1925b) made similar observations. 

Flattened stolons at the end of the stems as 

described by Thornely (1904) were not observed 

in the present material. 

Migotto (1996) re-examined the type material 

of this species and provides a synonymy. 

Distribution 

Tropical Indo-Pacific, Japan, southern Africa, 

tropical West Africa, Brazil. Type locality: Bass 

Strait, Australia. 

Sertularia borneensis Billard, 1925 

Fig. 43. 

?Sertularia maldivensis Borradaile, 1905: fig. 6a–b. – 

Stechow 1919: 97, fig. L1. 

Sertularia borneensis Billard, 1925a: 649, fig. 1D. – Billard 

1925b: 171, fig. 31. – Vervoort & Vasseur 1977: 60, figs 

26b & 27b. – Gibbons & Ryland 1989: 418, fig. 34. 

Sertularia west-indica. – Mammen 1965: 40, fig. 71. 

Sertularia westindica. – Cooke 1975: 100, pl. 5: fig. 1. 

Sertularia turbinata. – Vervoort & Vasseur 1977: 60, figs 

26–27. [Not Sertularia turbinata (Lamouroux, 1816)]. 

?Sertularia tongensis Stechow, 1919: 101, fig. N1. 

?Sertularia malayensis var. sorongensis Leloup, 1930b: 3, 

figs 1–3, pl. 1: fig. 1. 


Kei Islands Expedition stations: 67, on Macrorhynchia 

189 

Fig. 43. Sertularia borneensis Billard, 1925; station 67. A. 

Hydrothecal pair in lower region, scale bar 0.2 mm. B. Distal 

hydrothecae, same scale as A. C. Gonotheca, scale bar 0.5 

mm. – Scales: A–B = 0.2 mm; C = 0.5 mm. 

phoenicea, with gonothecae. – 107, on concretions, no 

gonothecae. 

Description 

Colonies with erect, simple, monosiphonic 

shoots, never branched. Stolons creeping, tubular, 

without internal pegs. Shoots reaching 

heights of 2 cm, at base relatively long ahydrothecate 

part ending in oblique hinge joint 

(length of this part equals 2–4 internode lengths 

of distal part), distal part bearing hydrothecae in 

opposite pairs, nodes transverse, mostly distinct, 

hydrothecal pairs in distal half of segment. Hydrothecae 

on lateral side of stem, proximal pairs 

not contiguous, most distal pairs contiguous in 

front, separate on rear side. 

Hydrotheca swollen in middle, hydrotheca 

broadest somewhat above middle, adnate for ½ 

or more of its adcauline length, adcauline side 

curved for nearly 90°, free adcauline wall nearly 

horizontal, abcauline wall oblique with slight 

double curvature (S-shape). Length of abcauline 

side 0.21–0.24 mm, diameter of opening (in side 

view) 0.1–0.11 mm. Hydrothecal opening slightly 

tilted towards above, margin with two con-

190 

spicuous lateral cusps, median adcauline cusp 

not observed, operculum composed of two 

valves, upper only slightly smaller than lower 

one. Bottom of hydrotheca oblique, adcauline 

wall elongated into tapering process. There is no 

intrathecal ridge. Hydranth with abcauline caecum. 

Gonotheca arising perpendicular to stem between 

lowest pair of hydrothecae, ovoid, 1.2 mm 

long, diameter 0.8 mm, with flat truncated end, 

wall with sharp, projecting spiral sculpture in 7– 

8 loops. 

Remarks 

There is no doubt that the present material is 

identical to S. borneensis as described and depicted 

in Billard (1925b) and Vervoort & Vasseur 

(1977). The fertile colony was also found on 

the same host as the type material and in nearly 

the same water depth. 

Vervoort & Vasseur (1977) – who also examined 

the type material of S. borneensis – synonymized 

this species with S. turbinata, although 

their material lacked an intrathecal ridge (see Fig. 

43). They explained its absence by the juvenile 

state of their material. This explanation appears 

now invalid, as also fertile material examined in 

this study lacked the ridge. Calder (1991) regarded 

S. borneensis as distinct from S. turbinata, 

but following Leloup (1960) he synonymized 

it with the Caribbean S. tumida Allman, 

1877. Sertularia borneenis is here kept separate 

from both S. turbinata and S. tumida. Similar 

conclusions were reached by Gibbons & Ryland 

(1989), who also regarded S. borneensis as valid. 

One sample from a nearby locality (station 

68), and thus sympatric with the other specimens 

of S. borneesis, contained a sertularid clearly 

referable to S. turbinata (see below, Fig. 44). 

Although I acknowledge the possibility that both 

could be only variants belonging to the same 

biological species, they are preferably kept separate 

because no intermediate forms are known so 

far. Indonesian morphotypes referable to either 

Sertularia borneensis or S. turbinata differ in the 

following details: Sertularia borneensis lacks an 

intrathecal ridge, has smaller hydrothecae (cf. 

Figs 43 and 44), the majority of the hydrothecal 

pairs are not contiguous, the bottom of the hy- 

P. SCHUCHERT 

drotheca is more oblique, the ahydrothecate part 

below the hinge joint is longer. 

Sertularia tumida, a species originally described 

from the tropical western Atlantic is insufficiently 

known because the gonothecae have 

never been described from the original region. 

Sertularia borneensis is therefore preferably 

kept separate from S. tumida (or its synonym 

S. westindica) as long as the gonothecae of 

S. tumida remain unknown from waters of the 

tropical Atlantic. Perhaps the gonothecae show 

significant differences and they might resemble 

more the South African S. longa, which has 

smooth gonotheacae but is otherwise hardly distinguishable. 

Mammen (1965, as S. west-indica) 

provides the only description and figure of the 

gonotheca for material attributed to the nominal 

species S. tumida, but for biogeographic reasons 

and also morphological differences Mammen’s 

material is better referred to S. borneenis or S. 

maldivensis. 

Sertularia borneensis differs from Atlantic S. 

tumida in the following details (cf. Calder 1991): 

it apparently lacks the small median tooth on 

the adcauline rim of the hydrotheca, it is never 

branched, and the hydrothecal bottom is more 

oblique. These are admittedly characters prone to 

variation and of very limited taxonomic value. If 

Atlantic S. tumida should prove to have the same 

gonothecae as found here for S. borneensis, both 

nominal species would be indistinguishable. Biogeographic 

arguments might then nevertheless 

be put forward to regard both species as distinct. 

Sertularia maldivensis Borradaile, 1905, an 

inadequately known species, appears conspecific 

with S. borneensis. Billard (1925b) did not discuss 

why he considered them distinct. Type material 

of Sertularia maldivensis must be examined 

before reliable conclusions can be drawn. 

Distribution 

Indonesia, Polynesia, perhaps also Maldives. 

Type locality: Indonesia, 2°25’S, 117°43’E, 34 

m, on Macrorhynchia phoenicea. 

Sertularia turbinata (Lamouroux, 1816) 

Fig. 44 

Dynamena turbinata Lamouroux, 1816: 180. 

Desmoscyphus brevicyathus Versluys, 1899: 40, figs 9–10.


Fig. 44. Sertularia turbinata (Lamouroux, 1816). Two pairs 

of hydrothecae. – Scale: 0.5 mm. 

Sertularia loculosa Bale, 1913: 121: pl. 12: figs 7–8, invalid 

name. 

Tridentata acuta Stechow, 1921: 231. 

Sertularia balei Briggs, 1922: 150. 

Not Sertularia turbinata. – Jarvis 1922: 341, pl. 24: fig. 8 [= 

Dynamena spec.]. 

Sertularia restricta Totton, 1930: 205. 

Geminella ceramensis. – Vannucci Mendes 1946: 570, pl. 4: 

figs 40–41. [Not Sertularella ceramensis Billard, 1925] 

Sertularia drachi Vannucci, 1949: 247. 

Sertularia turbinata. – Billard 1925b: 177, fig. 34. – Millard 

& Bouillon 1973: 76, fig. 9H. – Millard 1975: 312, fig. 

100B–C, E. – Gibbons & Ryland 1989: 425, fig. 39. – 

Hirohito 1995: 218, fig. 73d–f. – Migotto 1996: 78, figs 

14f-g. – Watson 1997: 52. – Medel & Vervoort 1998: 70, 

fig. 23, synonymy. 

Sertularia acuta. – Millard 1958: 19, figs 8A–F. 

Not Sertularia turbinata. – Garcia, Aguirre, & Gonzalez 

1980: 57, fig. 19 [= Sertularia tumida Allman, 1877]. 

Not Sertularia turbinata. – Vervoort & Vasseur 1977: 60 

figs 26–27 [= Sertularia borneensis Billard, 1925]. 

Tridentata tubinata. – Calder 1991: 110, fig. 60, synonymy. 


Kei Islands Expedition station 68, without gonothecae. 

191 

Diagnosis 

Similar to D. borneensis but with a horizontal 

intrathecal ridge on abcauline side and hydrothecal 

pairs always contiguous. 

Remarks 

See discussion under D. borneensis 

Distribution 

Tropical and subtropical waters. Type locality: 

Australasia. 

Sertularia trigonostoma Busk, 1852 

Fig. 45. 

Sertularia trigonostoma Busk, 1952: 392. – Bale 1884: 84, 

Fig. 45. Sertularia trigonostoma Busk, 1852; station 68. A. 

Stem internode with base of hydrocladium. B. Hydrocladial 

internode. – Scales: A = 0.2 mm; B = 0.1 mm.

192 

pl. 5: fig. 8. – Billard 1910: 21, fig. 7. – Billard 1925b: 

174. – Vervoort 1941: 217. – Watson 2000: 33, fig. 26A– 

E . 

Desmoscyphus obliquus Allman, 1888: 72, pl. 34: fig. 3–3a. 

Sertularia trigonostoma var. alternata Vervoort, 1959: 284, 

fig. 42. 


Kei Islands Expedition stations: 68. – 71; both colonies 

without gonothecae. 

Description 

Colonies erect, pinnate, up to 7 cm high. Stems 

monosiphonic, rather thick near base (0.7 mm), 

tapering distally, bearing alternate hydrocladia 

and two lateral rows of alternate hydrothecae, 

nodes distinct to indistinct, if present, alternately 

slanted and delimiting internodes. Stem internodes 

with three hydrothecae and an apophysis 

for hydrocladium, two hydrothecae on side of 

apophysis, one on opposite side, apophysis below 

lower hydrotheca. 

Hydrocladia straight, parallel, regular, arising 

at an angle of about 45° to axis, unbranched, 

longest ones in lower region of shoot, well demarcated 

from apophysis by transverse node, 

nodes more or less distinct, nodes inclined towards 

one side, two subopposite hydrothecae per 

internode; hydrothecae shifted to anterior side of 

internode, adnate on anterior side, separate on 

rear side. 

Hydrotheca adnate for most of its length, sacshaped, 

walls thick, abcauline side about 0.2 mm 

long, straight; opening directed upwards, margin 

with two blunt lateral teeth and sometimes a 

small adcauline median tooth. Opening elliptical, 

margin reinforced by thickened perisarc, operculum 

composed of two valves, difficult to observe. 

Connection of hydrotheca to internode 

very wide, thus hydrotheca without true floor. 

Gonothecae not present (see Watson 2000 for 

description). 

Remarks 

The hydranths in the present samples were not 

ideally preserved and it was not possible to decide 

reliably whether an abcauline caecum is 

present or not. Watson (2000) states that there is 

no caecum, although she also had badly preserved 

hydranths. If the absence of an abcauline 

P. SCHUCHERT 

caecum can be corroborated, this species should 

be referred to the genus Dynamena. 

Distribution 

Tropical Indo-Pacific, Red Sea, tropical western 

Africa. Type locality: Torres Strait, Australia. 

Sertularia malayensis Billard, 1925 

Fig. 46. 

Sertularia malayensis Billard, 1925a: 649. – Billard 1925b: 

173, fig. 32. – Vervoort & Vasseur 1977: 57, fig. 25. – 

Hirohito 1983: 49, fig. 21. – Gibbons & Ryland 1989: 

421, fig. 37. – Hirohito 1995: 215, fig. 72a–c. 


Kei Islands Expedition station 26, several shoots without 

gonotheca on S. quadridens var. timorensis. 

Description 

Colonies forming erect unbranched shoots without 

hydrocladia, height 2–4 mm. Stolons creeping, 

ramified. Stem thin (about 0.1 mm), with 

occasional oblique or transverse nodes. Hydrothecae 

strictly opposite, each pair contiguous on 

frontal side, separated at rear. 

Hydrotheca tubular, upper and underside converging 

and end thus duck-bill shaped, adcau- 

Fig. 46. Sertularia malayensis Billard, 1925. Pair of hydrothecae. 

– Scale: 0.1 mm.


line wall adnate for 1/3 of its length, abcauline 

curved, about 0.18 mm long, adcauline wall 

quite sharply bent where becoming free, margin 

with two long, pointed lateral teeth, operculum 

formed by two valves, upper one much larger, 

lower valve not distinctly delimited from hydrotheca, 

distal end of hydrotheca very soft 

and often distorted; floor of hydrotheca complete, 

lower end of adcauline wall forming short, 

pointed process. Hydranth with about 8 tentacles, 

with small abcauline caecum. 

Gonothecae not observed (according to Hirohito 

1983: pear-shaped, smooth walls, with truncate 

end and opening on short collar). 

Remarks 

The hydrothecal margin of this small and delicate 

species is rather flimsy and the generic characters 

are very difficult to see. 

Leloup (1930b) described a variant of this 

species from New Guinea as Sertularia malayensis 

var. sorongensis. Leloup’s material was 

juvenile and not reliably identifiable. It resembles 

much more S. borneensis, to which it most 

probably belongs. Leloup (1930b: 6) also discusses 

the differences of his variant to S. borneensis, 

but all tabulated characters are of very 

limited value in discriminating Sertularia species. 

Distribution 

Indonesia, Japan, French Polynesia, Fiji. Type 

locality: Borneo, 2°25’S, 117°43’E, 40–50 m, on 

hydroids. 

Symplectoscyphus macrocarpa (Billard, 1918) 

Fig. 47. 

Sertularella macrocarpa Billard, 1918: 23, fig. 3A–B. – 

Billard 1925b: 162, fig. 25, pl. 7: figs 16–17. 



Description 

Colonies erect, up to 2 cm high, pinnate. Stem 

and hydrocladia zigzag, both with identical structure, 

stem with about 2–3 hydrothecae between 

successive hydrocladia of one side. 

193 

Fig. 47. Symplectoscyphus macrocarpa (Billard, 1918). A. 

Two hydrothecae. B. Gonothecae. – Scales: A = 0.2 mm; B 

= 0.5 mm. 

Hydrocladia long, may reach the same length 

as stem, inserting below hydrothecae of stem, 

nodes oblique, often indistinct or absent. 

Hydrotheca cylindrical, adnate for 2/5 of its 

adcauline length, free part held at about 60° 

to internode, abcauline wall almost straight to 

slightly concave, 0.35–0.4 mm, abcauline side 

sharply curved where becoming free; opening 

diameter 0.14–0.16 mm, margin with three 

cusps, one median adcauline and two lateroabcauline; 

operculum composed of three flaps, 

hydrothecal floor not complete, reaching mostly 

only to middle. Gonothecae numerous, on hydrocladia.

194 

Gonotheca elongate amphora-shaped, walls 

smooth, length 2–2.2 mm, maximal diameter 

above middle 0.5–0.6 mm, terminal opening on a 

narrow tubular neck, length 0.2 mm. 

Distribution 

Moluccas, Kei Islands. Type locality: Moluccas, 

3.450°S, 131.008°E, 567 m, on fine grey-yellow 

mud. So far only known from deeper waters 

(370–567 m). 

Family Thyroscyphidae 

Thyroscyphus bedoti Splettstösser, 1929 

Fig. 4. 

Lytoscyphus junceus. – Pictet 1893: 37, pl. 2: figs 32–33. 

[Not Thyroscyphus junceus (Allman, 1876)] 

Thyroscyphus bedoti Splettstösser, 1929: 42, figs 36–38, 

new name. 

?Thyroscypus macrocytharus. – Watson 2000: 37, fig. 29A. 


MHNG INVE 25030, as Lytoscyphus junceus, material described 

in Pictet (1893), type material of Thyroscyphus 

bedoti Splettstösser, 1929. 

Description 

Colony erect, up to 4 cm high, unbranched, without 

hydrocladia, with alternately oblique nodes, 

internodes smooth, of variable length, with subterminal 

apophysis for hydrothecae, apophysis 

demarcated from hydrotheca by node. Hydrothecae 

alternating, in two rows, in one plane. 

Pedicel of hydrotheca annulated or not. Mature 

shoots with numerous gonothecae of different 

developmental stages, almost every hydrotheca 

with one gonotheca below it 

Hydrotheca campanulate, radially symmetric 

to bilaterally symmetric, straight abcauline side 

and convex adcauline side, depth 1.1–1.2 mm, 

diameter at opening 0.6 mm, walls smooth; margin 

with 4 shallow cusps or almost even; operculum 

pyramidal with four flaps, mostly lost; diaphragm 

an oblique perisarcal ring, more developed 

on adcauline side. Hydranth with about 25 

tentacles. 

Gonotheca 1.4 mm long, diameter 0.7 mm, 

cylindrical, tapering into pedicel below, distal 

half of gonotheca slightly undulated. 

P. SCHUCHERT 

Fig. 48. Thyroscyphus bedoti Splettstösser, 1929; after type 

material. A. Part of stem with hydrothecae and gonothecae of 

various developmental stages. B. Mature gonotheca, same 

scale as A. – Scale: A–B = 0.5 mm. 

Remarks 

Pictet (1893) allocated unbranched but mature 

colonies of a Thyroscyphus species to Lytoscyphus 

junceaus (Allman, 1876). Thyroscyphus 

junceus (Allman, 1874), an obvious synonym of 

T. fruticosus, forms large and branched plumes 

and it is unlikely that Pictet’s material belongs 

this species. In his detailed study of the Thyroscyphidae, 

Splettstösser (1929) therefore proposed 

a new name for Pictet’s species: Thyroscyphus 

bedoti. 

Thyroscyphus bedoti shows some resemblance 

to T. macrocyttarus (Lamouroux, 1824). 

This species has recently been re-described 

(Watson 1994) and synonymized with T. marginatus 

(Bale, 1884) (= T. balei Calder, 1983). 

Thyroscyphus macrocyttarus had been reported 

until recently only from temperate waters of 

southern and south-western Australia. Its colo-


nies are characterized as occurring either as stolonal 

forms or as unbranched stems that have all 

their hydrothecae on one side only. The perisarc 

of its internodes are usually undulated. These 

characteristics separate it clearly from T. bedoti, 

which is a species of warm waters and which has 

two rows of hydrothecae. Watson (2000) allocated 

material from tropical waters near Darwin 

to T. macrocyttarus (as T. macrocytharus), although 

it had two rows of alternate hydrothecae 

and rather smooth internodes. Her material was 

growing on sponges. Due to these morphological, 

substrate, and biogeographic differences, I 

think that Watson’s material from Darwin could 

also belong to T. bedoti, although it has more 

pointed cusps and the hydrothecae are considerably 

smaller. 

Distribution 

Eastern Indonesia, ? northern Australia. Type 

locality: Batumera, Bay of Ambon, Moluccas, 

Indonesia; littoral zone, on coarse sand. 

Thyroscyphus fruticosus (Esper, 1793) 

Fig. 49. 

Spongia fruticosa Esper, 1793: 188. 

Thyroscyphus vitiensis Marktanner-Turneretscher, 1890: 

210, pl. 3: fig. 10. – Gibbons & Ryland 1989: 427. 

Campanularia thyroscyphiformis Marktanner-Turneretscher, 

1890: 206, pl. 3: fig. 4. – Rees & Vervoort 1987: 

67. 

?Campanularia juncea Allman, 1876: 260, pl. 11: figs 3–4. 

Campanularia juncea. – Thornely 1904: 113, text. figs 1–3, 

pl. 1: fig. 1a–b. 

Not Lytoscyphus junceus. – Pictet 1893: 37, pl. 2: figs 32–33 

[= Thyroscyphus bedoti Splettstösser, 1929] 

Lytoscyphus fruticosus. – Stechow & Müller 1923: 465, pl. 

27: fig. 6. 

Thyroscyphus fruticosus. – Splettstösser 1929: 7, figs 1–11, 

13–27. – Vervoort 1941: 202. – Ralph 1961a: 754, fig. 

1a. – ? Millard 1975: 323, fig. 104. – Gibbons & Ryland 

1989: 425, fig. 40. – Watson 2000: 38, fig. 29D. 

Thyroscyphus ramosus. – Mammen 1965: 30, fig. 63. [Not T. 

ramosus Allman, 1877] 


Kei Islands Expedition stations: 11, with gonothecae. – 19, 

with gonothecae. – 43. – 67, with gonothecae. – 86. – Kei 

Islands Expedition, Banda Islands, Lonthoir, 07 Jun 1922, 

with gonothecae. 

Description 

Colony erect, pinnate, 5–20 cm, stems often in 

195 

Fig. 49. Thyroscyphus fruticosus (Esper, 1793); A & C–D, 

station 19; B, station 11. A. Colony silhouette. B. Hydrotheca 

variant with marginal cusps and operculum. C. Two 

hydrothecae with smooth margin and a male gonotheca, 

same scale as B. D. Presumed female gonotheca, same scale 

as B. – Scales: A = 1 cm; B–D = 0.5 mm. 

dense clusters. Stem thick, stiff, monosiphonic, 

without nodes, with two lateral rows of hydrothecae, 

hydrothecae alternate and in one plane.

196 

Hydrocladia alternate, in one plane, long and 

quite straight, usually unbranched, only rarely 

branched, nodes indistinct or absent, hydrothecae 

on a broad and short apophysis. Hydrotheca 

with short pedicel, without distinct node demarcating 

it from apophysis. 

Hydrotheca campanulate, 1–1.2 mm deep, diameter 

at opening 0.5–0.6 mm, slightly bilateral 

symmetric through bulging upper side and almost 

straight underside, at base a distinct diaphragm, 

margin either smooth or with four indistinct, 

broad cusps; below rim an internal annular 

ridge, operculum pyramidal and composed of 

four flaps, operculum frequently lost. Inside of 

hydrotheca covered by thin tissue layer with few 

large nematocysts. Hydranth with about 30 tentacles. 

Gonothecae on stem and hydrocladia, developing 

below hydrothecae on their apophyses, 

1.8–2.4 mm, oblong oval, basal part tapering, end 

truncated, wall smooth. Male more slender, female 

thicker and end wider. 

Remarks 

See comments under T. torresii. The hydrothecae 

in living colonies have a characteristic rosepink 

colour, which is lost in preserved material 

(Millard 1975, Watson 2000). 

Distribution 

Tropical Indo-West Pacific, New Zealand, southern 

Africa, western Africa, Mediterranean. Type 

locality: Unknown. 

Thyroscyphus torresii (Busk, 1852) 

Fig. 50. 

Laomedea torresii Busk, 1852: 402. 

Campanularia Torresii. – Bale 1884: 52, pl. 11: fig. 3. 

Tyroscyphus simplex Allman, 1888: 25, pl. 13: figs 1–2. 

Tyroscyphus regularis Jäderholm, 1896: 9, pl. 1: fig. 8. 

Cnidoscyphus torresii. – Splettstösser 1929: 70, figs 68–77, 

map 2. – Vervoort 1941: 204, fig. 1. – Vervoort 1993: 

104. 

Thyroscyphus torresi. – Jäderholm 1903: 273, pl. 12: fig. 6. 

– Stechow & Müller 1923: 466. – Watson 2000: 37, fig. 

29B–C. 

Thyroscyphus fruticosus. – Mammen 1965: 31, fig. 64. [Not 

T. fruticosus (Esper, 1793)] 


Kei Islands Expedition stations: 15. – 18. – 20. – 40. – 64. – 

P. SCHUCHERT 

Fig. 50. Thyroscyphus torresii (Busk, 1852); station 65. A. 

Two internodes with hydrothecae. B. Hydrotheca and gonotheca, 

same scale as A. – Scale: A–B = 0.5 mm. 

65, with gonothecae. – 68. – 71. – 74. – 90. – 102. – 103. – 

104. – 106. 


Similar to Thyroscyphus fruticosus, but epidermal 

lining of hydrotheca with a pad containing a 

dense cluster of large nematocysts; stems shorter 

(up to 10 cm); hydrocladia with distinct nodes, 

nodes alternately inclined left and right; hydrotheca 

demarcated by distinct node from apophysis, 

rim of hydrotheca with four distinct cusps, 

operculum regularly present. Diaphragm of hydrotheca 

more unequally developed. Gonotheca 

more barrel-shaped, 1.1 mm, lateral wall undulated 

in distal half.


Remarks 

Thyroscyphus fruticosus and T. torresii share 

many characters, particularly in size of colony, 

habit and choice of habitat (Watson 2000). Their 

morphological similarity has probably led to 

some past confusion of the species. In the present 

Indonesian material, just as in the Australian one 

described by Watson (2000), T. torresii is relatively 

easy to distinguish from T. fruticosus 

through the distinct nodes of the hydrocladia and 

the distinct marginal cusps of the hydrotheca. 

Other populations may show intermediate characters. 

The figure of T. fruticosus in Millard 

(1975, fig. 104) resembles more T. torresii. The 

colour of the African material, however, matches 

T. fruticosus. Living colonies of T. fruticosus are 

rose-pink, while T. torresii are golden-yellow to 

golden-brown (Watson 2000). Using this colour 

information and his figures, it is evident that 

Mammen (1965) confounded the two species. 

His material identified as T. ramosus is actually 

T. fruticosus, while his T. fruticosus material 

belongs to T. torresii. A good character to distinguish 

both species are the large nematocyst batteries 

in the interior lining of the hydrothecae of 

T. torresii (Splettstösser 1929). However, these 

nematocyst clusters are often lost in dredged 

material. Splettstösser (1929) used this character 

to establish the new genus Cnidoscyphus. 

The validity of this genus was emphasized by 

Vervoort (1993), but other recent authors, e.g., 

Bouillon (1985a), Calder (1983), and Watson 

(2000), did not use it. Such thick nematocyst pads 

are also found in many species of the Sertulariidae, 

the closest relatives of the Thyroscyphidae, 

and thus likely represent a plesiomorphy. Because 

plesiomorphic traits are not suitable for 

detecting monophyletic groups, the genus Cnidoscyphus 

is not used here either. 

Mature gonothecae of this species have been 

described by Jäderholm (1903) and Splettstösser 

(1929). The gonothecae observed in the present 

material confirmed Jäderholm’s findings in that 

their distal half has an undulated wall. The male 

gonothecae may be more slender and smooth as 

Splettstösser’s (1929) figures suggest. 

Distribution 

Indonesia, northern and western Australia, 

197 

Queensland, China Sea, Mergui Archipelago. 

Type locality: Prince of Wales Channel, Torres 

Strait, Australia. 

Thyroscyphus sibogae Billard, 1930 

Fig. 51. 

Thyroscyphus sibogae Billard, 1930: 230, fig. 1. – 

Pennycuik 1959: 198. – Gibbons & Ryland 1989: 427, 

fig. 41. 


Kei Islands Expedition station 60, without gonothecae, few 

shoots on a synascidian. 

Description 

Colony forming erect shoots, up to 1 cm high, 

unbranched, without hydrocladia, with indistinct 

alternately oblique nodes, internodes smooth or 

slightly undulated, with subterminal apophysis 

for hydrothecae, apophysis demarcated from hydrotheca 

by node. Hydrothecae alternating, in 

one plane. 

Fig. 51. Thyroscyphus sibogae Billard, 1930. Hydrotheca. – 

Scale: 0.2 mm

198 

Hydrotheca campanulate, bilaterally symmetric, 

straight abcauline side and convex adcauline 

side, depth 0.5–0.6 mm, diameter at opening 0.33 

mm, lateral wall with distinct transverse corrugation 

(about 6 bulges), margin with 4 pointed 

cusps and deep, round embayments between 

them, operculum pyramidal with four flaps, diaphragm 

an oblique perisarcal ring, more developed 

on adcauline side. Pedicel of hydrotheca 

annulated or not. 

Gonothecae absent, according to Gibbons & 

Ryland (1989) arising from hydrothecal apophyses, 

pedicellate, annulated, usually directed horizontally 

and down, not in the same plane as 

the remainder hydrothecae; obovoid, truncated 

distally; aperture with four cusps and operculum 

of four flaps. 

Remarks 

The corrugated, small hydrothecae distinguish 

this species from all other congeners in the Indonesian 

region. 

Distribution 

Eastern Indonesia, Great Barrier Reef, Fiji. Type 

locality: Timor. 

Family Syntheciidae 

Synthecium flabellum Hargitt, 1924 

Fig. 52. 

Synthecium flabellum Hargitt, 1924: 497, pl. 6: fig: 24. – 

Gravier-Bonnet 1979: 41. 

Synthecium samauense in part Billard, 1925a: 646, fig. 1A 

(not others). – Billard 1925b: 132, fig. 7C–E, pl. 7: fig. 3 

(not others). 

Sertularia tubitheca. – Pictet 1893: 51–52, pl. 2: figs 44–45. 

– von Campenhausen 1896b: 309. [Not Synthecium tubithecum 

(Allman, 1877)] 

?Synthecium megathecum Billard, 1925a: 648. – Billard 

1925b: 130, fig. 6, pl. 7: fig. 2. 


Synthecium flabellum Hargitt, 1924, NMNH reg. number 

USNM 42514, in formaldehyde, overgrown by Hebella 

spec. – Synthecium samauense Billard, 1925, ZMA number 

Coel 3835, Siboga station 60, tube labelled by Billard as 

female type, only colonies with gonothecae belong to S. 

flabellum, infertile ones are S. samauense. 


ZMA no. Coel 3833, Siboga station 274, identified as S. 

P. SCHUCHERT 

samauense by Billard, fertile female colonies. – Kei Islands 

Expedition, Neira Island, Banda Islands, Indonesia, 10 m, 

coll. 5 Jun 1922, few stems on black sponge and hydroids, 

with female gonothecae, overgrown by Hebella sp. – MHNG 

INVE 32194, as Sertularia tubitheca, Ambon, 16 Aug 1890, 

material of Pictet (1893), overgrown by Hebella sp. 

Description 

Colonies pinnate, 2–4 cm in height. Stolons tubular, 

thick. Stems flexible, with opposite pairs of 

hydrocladia, 4–6 per side, stem without nodes, 

hydrocladia without distinct apophysis, with 2 or 

more pairs of opposite hydrothecae between successive 

hydrocladia. 

Hydrocladia straight, unbranched, some with 

terminal tendrils, up to 2.5 cm long, nodes rare, 

with two rows of opposite hydrothecae, the pairs 

of hydrothecae not contiguous, successive hydrothecae 

of one row not in contact and quite 

distant, the median planes of the two rows form 

an angle < 180°. 

Hydrotheca tubular, recurved 60–75°, opening 

inclined upwards, abcauline side adnate for 3/ 

5–2/3 of its length, opening diameter 0.25–0.30 

mm (mean 0.27, S.D. 0.017, n = 6, 3 colonies), 

length free part of adcauline side 0.25–0.40 mm, 

length adnate part 0.57–0.67 mm. Margin of 

opening planar or sinuous, slightly everted, often 

renovated several times, without operculum. 

Only female gonothecae seen, developing 

from within stem hydrothecae, 0.9–1.1 mm 

long, diameter 0.7–0.8 mm, egg-shaped, with 

distal nipple-shaped process, not flattened, walls 

smooth; terminal opening small; containing one 

egg of 0.5–0.6 mm diameter. 

Nematocysts: I, abundant tentacular capsule, 

almond-shaped, 5.5 x 1.5 µm, probably a mastigophore. 

II, large isorhiza, (40–43) x (10–11) 

µm. III, smaller isorhiza 17 x 5 µm. 

Remarks 

Synthecium flabellum Hargitt, 1924 is a little 

known species and Gravier-Bonnet (1979) suggested 

that it could be conspecific with S. samauense 

Billard, 1925. Re-examination of the 

type material of Synthecium flabellum and S. 

samauense showed that part of Billard’s type 

material of S. samauense indeed belongs to S. 

flabellum, while the remainder of the type mate-


Fig. 52. Synthecium flabellum Hargitt, 1924; A–C, Banda Islands; D–E, type material. A. Colony silhouette. B. Part of stem, 

hydrocladia, and female gonotheca. C. Pair of hydrothecae. D. Pair of hydrothecae, same scale as C. E. Part of stem with female 

gonothecae. – Scales: A = 1 cm; B & E = 0.5 mm; C = 0.2 mm 

rial belongs to S. samauense sensu lato. For more 

details see under S. samauense. 

Especially the characteristic female gonothecae 

resembling a lemon was important for recognizing 

the species (Fig. 52B). The male gonothecae 

of this species are so far unknown, but it 

is very probable that Synthecium megathecum 

Billard, 1925b is nothing but the male of S. 

flabellum. Billard kept Synthecium megathecum 

separate from other congeners on account of 

199 

its large hydrothecae. Billard (1925b) gives for 

Synthecium megathecum a hydrotheca diameter 

of 0.28–0.33 mm, which largely overlaps with 

the here observed values for female Synthecium 

flabellum (0.25–0.30 mm). 

Distribution 

Philippines, Indonesia. Type locality: Philippine 

Islands.

200 

Synthecium samauense Billard, 1925 

Fig. 53. 

Synthecium samauense in part Billard, 1925a: 646, fig. 1B. – 

in part Billard 1925b: 132, fig. 7A-B. – Vervoort & 

Vasseur 1977: 24, figs 10–13. – Gibbons & Ryland 1989: 

398, fig. 16. 


Synthecium samauense Billard, 1925, ZMA no Coel 3835, 

Siboga station 60, Haingsisi; comprises two tubes: one tube 

labelled by Billard as male type containing several male 

colonies as depicted in Billard (1925b: fig. 7A–B), but also 

one colony with female gonothecae; this female colony 

placed in new tube and designed here as lectotype. The tube 

labelled by Billard as female type contains several colonies: 

some fertile females with distinctly larger hydrothecae and 

some distinctly more gracile ones without gonothecae. The 

latter are presumably also S. samauense, while the fertile 

colonies are clearly S. flabellum Hargitt, 1924. 


ZMA Coel 3835, Siboga station 282, as Synthecium samauense, 

with gonotheca, soft tissue not well preserved 

but shape and dimensions conforms with lectotype. – Kei 

Islands Expedition, Waling, Banda Island, Indonesia, 20 m, 

coll. 11 Jun 1922, on sponge, several stems with female 

gonothecae, some empty. 


Like Synthecium flabellum, but colonies 1–2 cm, 

hydrotheca distinctly narrower, diameter of 

opening 0.16–0.20 mm (mean 0.175, S.D. 0.017, 

n = 15, 4 colonies), length of free adcauline wall 

0.15–0.31 mm, length adnate part 0.48– 0.55 

mm, occasionally some hydrothecal pairs contiguous. 

Female gonotheca ovoid-lenticular, 

broader side horizontal, smooth walled or slightly 

undulated, length 1.1 mm, thickness 0.65 mm, 

without nipple-shaped distal process, opening 

sometimes with indistinct collar, one egg of 0.5– 

0.6 mm. Male gonothecae elongated pod-shaped, 

1.6 mm long, somewhat flattened, broader side 

held horizontally, wall with or without gentle 

undulation, terminal opening, pedicel within hydrotheca 

and not at right angle to body of gonotheca. 

Remarks 

When describing Synthecium samauense, Billard 

(1925b) noted that the dimensions of the hydrothecae 

in his material permitted the distinction of 

two separate morphotypes, this even within the 

specimens from the type locality. Billard interpreted 

this as sexual dimorphism as his obvious 

P. SCHUCHERT 

female colonies belonged to the morphotypes 

with larger hydrothecae. Vervoort & Vasseur 

(1977) re-examined Billard’s type material from 

Siboga station 60 and found no female gonothecae 

and all dimensions of the investigated 

material were rather homogeneous. The female 

gonothecae observed by Vervoort & Vasseur 

(1977) in material from Moorea deviated clearly 

from the one depicted in Billard (1925b) as they 

lacked the nipple-shaped process and they were 

flattened. Identical material from Fiji was later 

described by Gibbons & Ryland (1989). Because 

the material of Synthecium species from the Kei 

Islands expedition presented considerable difficulties 

for identification, and because there were 

also two sets of colonies with distinctly different 

dimensions and gonothecae, I compared it to 

Billard’s type material, the non-type material 

from the Siboga collection and the holotype of 

Synthecium flabellum Hargitt, 1924 as well. 

Re-examination of the type material of Synthecium 

samauense convinced me that it is composed 

of two species. The type material from 

Siboga station 60 is separated into two tubes with 

labels made by Billard: one labelled as female, 

one as male. The tube labelled as female contains 

several stems, some of them with gonothecae. 

The infertile stems in this tube are clearly distinct 

as they have narrower hydrothecae. It seems thus, 

that Vervoort & Vasseur (1977) did not have the 

complete type series at hand. In fertile female 

stems, the eggs are clearly visible in the gonothecae, 

and these specimens are identical to the 

holotype of Synthecium flabellum Hargitt, 1924. 

The infertile stems are here regarded as belonging 

to S. samauense. The sample labelled as 

containing male colonies contains also several 

stems, most of them with male gonothecae as 

figured in Billard (1925b). The dimensions of the 

hydrothecae do not vary significantly and the 

specimes are distinguishable from the larger S. 

flabellum. One of the fertile colonies in the tube 

reportedly containing male S. samaunese, however, 

has short gonothecae and closer inspection 

(temporary clearing in 50% lactic acid) revealed 

it to be female (Fig. 53F). Because it is evident 

that Billard’s type material of S. samauense contains 

two species, this female stem was chosen as 

lectotype and placed in a separate tube. The 

remainder of the tubes are the stems with male


Fig. 53. Synthecium samauense Billard, 1925; A–D, from Banda Islands; E–F, lectotype; G, male type colony. A. Colony 

silhouette. B. Three pairs of hydrothecae, note variation of separation and length of free part. C. Female gonothecae. D. Female 

gonotheca seen from broad (upper) side with tissue inside (incipient egg stippled dark), same scale as B. E. Pair of hydrothecae, 

same scale as B. F. Female gonotheca in side view, egg stippled dark, same scale as B. G. Pair of male gonothecae in side view, 

same scale as C. – Scales: A = 1 cm; B, D–F = 0.2 mm; C, G = 0.5 mm. 

201

202 

gonothecae. By choosing the female colony with 

the smaller dimensions as lectotype, Billard’s 

species remains valid and does not become a 

subjective synonym of S. flabellum. Furthermore, 

Vervoort & Vasseur’s (1977) and Gibbons 

& Ryland’s (1989) identifications remain correct 

by this procedure. 

The validity of both S. samauense and S. flabellum 

is underlined by the sympatric occurrence 

of their respective morphotypes (Siboga station 

60, Banda Islands). Synthecium samauense and 

S. flabellum can be distinguished on account 

of the differently shaped female gonothecae and 

the dimension of the hydrotheca. Synthecium 

samauense has a lenticular female gonothecae, 

while S. flabellum has a spherical one with a 

nipple-shaped process. The hydrothecal diameter 

of S. samauense is like most of the congeners 

of the region (0.16–0.20 mm), while S. flabellum 

has a diameter of 0.25–0.30 mm. The diameters 

are more obviously different than other dimensions 

of the hydrotheca. 

With its new, restricted scope, Synthecium 

samauense is not easy to separate from S. orthogonium 

or S. campylocarpum, at least for the 

material encountered in this study. The regular 

corrugation of the gonothecae of S. orthogonium 

is the only reliable character to separate it from S. 

samauense. Synthecium campylocarpum forms 

larger colonies (6 cm versus 1–2 cm) and has 

male gonothecae with a pedicel inserting at a 

right angle. 

More material of all morphotypes must be 

examined to consolidate the validity of all Synthecium 

species discussed here. As shown by 

Watson (2000), life observation of colour and 

ecology might provide additional and more reliable 

characters to separate them. 

Distribution 

Indonesia, Polynesia, New Caledonia. Type locality: 

Hainsisi, Indonesia. 

Synthecium orthogonium (Busk, 1852) 

Fig. 54. 

Sertularia orthogonia Busk, 1852: 390. 

Synthecium orthogonium. – Stechow & Müller 1923: 465. – 

Watson 2000: 41, fig. 32A–F, table 4. 

P. SCHUCHERT 

Fig. 54. Synthecium orthogonium (Busk, 1852). A. Colony 

silhouette. B. Part of stem with two hydrocladia and gonotheca 

with smooth underside. C. Hydrothecae of hydrocladium. 

D. Gonotheca in side view, upper and underside are 

corrugated, same scale as B. E. Gonotheca seen from broad 

side, same scale as B. – Scales: A = 1 cm; B, D–E = 0.5 mm; 

C = 0.2 mm. 

Not Synthecium orthogonium. – Bale 1888: 767. – Bale 

1924: 250. [= S. campylocarpum] 

Synthecium patulum. – Billard 1925b: 125, figs 2–3. – 

Vervoort 1941: 199, fig. 2. 

Synthecium patulum var. elongatum Billard, 1925b: 128, 

fig. 4. [Not Synthecium patulum (Busk, 1852)]



Kei Islands Expedition station 67, on Idiellana pristis¸ several 

fertile plumes. 

Description 

Colonies pinnate, up to 3 cm. Stolons tubular, 

thick. Stems with opposite hydrocladia, 6–8 per 

side, stem with indistinct transverse nodes, hydrocladia 

at distal end of internodes, without 

distinct apophysis, 1–3 pairs of opposite hydrothecae 

per stem internode bearing hydrocladia. 

Hydrocladia straight, unbranched, up to 1 cm 

long, nodes rare, with two rows of opposite hydrothecae, 

the pairs of hydrothecae not contiguous, 

successive hydrothecae of one row not in 

contact but rather close, the median planes of the 

two rows form an angle < 180°. 

Hydrotheca tubular, recurved 90°, openingplane 

parallel to hydrocladial axis, abcauline side 

adnate for 2/3, opening diameter 0.14–0.15 mm, 

length free part of adcauline side 0.20–0.25 mm, 

length adnate part 0.45 mm. Margin of opening 

planar and not sinuous, slightly everted, often 

renovated several times, without operculum. 

Gonothecae arise from within stem hydrothecae, 

1.2 mm long, oblong ovoid, somewhat flattened, 

broader sides horizontal, either both sides 

corrugated or upper side corrugated and underside 

smooth, corrugations fading out towards 

periphery, if both sides corrugated, the crests do 

not meet at the narrow sides, the crests of both 

sides are out of phase; opening terminal, small. 

Nematocysts: I, abundant tentacular capsule, 

almond-shaped, 5.5 x 1.5 µm, probably a mastigophore. 

II, large isorhiza, holotrichous, (40– 

43) x (10) µm, on hydranth body, thread well 

visible in un-discharged capsule. III, smaller 

isorhiza, (19–23) x (5–6) µm, on hydranth body. 

Remarks 

The sample identified here as S. orthogonium 

agreed well with the figures and dimensions 

given in Watson (2000) and there can be little 

doubt that they belong to the same species. 

Because Busk (1852) himself somewhat 

doubted the validity of Synthecium orthogonium 

(Busk, 1852), most authors referred this species 

to S. patulum (Busk, 1852) (e.g., Billard 1925b, 

Rees & Vervoort 1987). Watson (2000) showed 

203 

that both are distinct species, although separating 

the two is not trivial. Synthecium patulum is 

restricted to temperate waters of southern and 

south-eastern Australia, while S. orthogonium is 

a species occurring in tropical waters. Living 

colonies of S. patulum have a characteristic reddish-purple 

colour, which is, however, lost in 

preserved material. 

Synthecium campylocarpum Allman, 1888 

has likewise been synonymized by many authors 

with S. patulum and S. orthogonium (e.g., Billard 

1925b, Rees & Vervoort 1987). Watson (2000) 

re-examined type material and provided evidence 

that it can be distinguished from both of 

them, although the differences are minimal (see 

remarks under S. campylocarpum). 

There is little, except for biogeographic arguments, 

to distinguish Synthecium orthogonium 

(Busk, 1852) from S. tubithecum (Allman, 1877), 

a species of the warm Atlantic Ocean (see Calder 

1991 for description). The two could be indistinguishable, 

but not necessarily belong to the same 

biological species. 

Distribution 

Indonesia, northern Australia, ?Queensland, 

?Papua New Guinea. Depth range: usually less 

than 100 m, one record of 400 m (Billard 1925b). 

Type locality: Torres Strait, Australia. 

Synthecium campylocarpum Allman, 1888 

Fig. 55. 

Synthecium campylocarpum Allman, 1888: 78, pl. 37: figs 1 

& 1a–c. – von Campenhausen 1896b: 310, fig. 6. – 

Billard 1910: 26, fig. 10. – Ralph 1958: 347, fig. 15c–g. 

– Watson 2000: 40, figs 30A–G, 31A–C. 

Synthecium orthogonium. – Bale 1888: 767. – Bale 1924: 

250. 

Synthecium patulum. – Millard & Bouillon 1973: 64, fig. 8J. 

– Millard & Bouillon 1975: 12, fig. 3C–E. [Not Synthecium 

patulum (Busk, 1852)] 


Kei Islands Expedition, Samalon Island, Sulawesi, Ujungpandang, 

Indonesia, 25 m, sandy bottom, coll. 29 Jun 1922, 

one plume 6 cm and hydrocladium with male gonothecae. 


Like Synthecium orthogonium, but stems larger 

(6 cm), stem thick, lower half of stem without 

hydrothecae between successive hydrocladia,

204 

apophyses demarcated by node; hydrotheca usually 

less curved (60°) with opening inclined towards 

above, margin usually sinuous. Measurements: 

hydrothecal opening diameter 0.18–0.21 

mm, free adcauline part 0.28–0.31 mm, adnate 

part 0.50–0.55 mm. Large isorhiza (49) x (12– 

13) µm, smaller isorhiza 24 x 6 µm. 

Description of gonotheca 

Only male gonothecae seen, develop inside hydrocladial 

hydrothecae, pod-shaped, flattened, 

1.7 mm long, diameter in middle 0.7 mm, pedicel 

inserted at right angle slightly above lower end, 

broad sides gently undulated, upper end pointed 

with small opening. 

P. SCHUCHERT 

Fig. 55. Synthecium campylocarpum Allman, 1888. A. Colony silhouette, note apical tendril on second hydrocladium on right. 

B. Internodes of distal part of stem. C. Typical hydrothecae. D. More rare hydrothecae with sharper bend; from same colony 

and scale as shown in C. E. Hydrothecal margin with typical sinuous outline. F. Pair of male gonothecae, twisted so that broad 

sides are in plane of view, same scale as B. – Scales: A = 1 cm; B & F = 0.5 mm; C-D = 0.2 mm; E = 0.1 mm. 

Female gonothecae not seen, according to 

Ralph (1958) and Watson (2000) resembling the 

one of S. orthogonium. 

Remarks 

The identification of this material as Synthecium 

campylocarpum was largely influenced by 

Watson (2000), but I am not sure whether the 

differences from S. orthogonium are significant 

or represent intraspecific variation due to larger 

grown colonies. The material strongly resembles 

S. orthogonium and the traits of the trophosome 

used to distinguish it from the latter species are 

given in the section “Differential diagnosis”. 

The most important differences are the larger


stem, the less curved hydrothecae, and the sinuous 

hydrothecal margin. Although these traits 

generally agree with Watson’s material of S. 

campylocarpum, they also show variation within 

the same plume that approached the characteristics 

of S. orthogonium. Some few hydrothecae 

are longer and curved for 90° (Fig. 55D), while 

other hydrothecae quite frequently lack the sinuous 

margin. A quite distinct difference to the 

material identified here as S. orthogonium is 

the paucity of cauline hydrothecae, even in 

internodes bearing hydrocladia. Only more distal 

stem internodes have hydrothecae (Fig. 55A–B). 

The figures by Allman (1888) show a similar 

situation. However, Watson (2000) indicates that 

also the basal internodes of S. orthogonium may 

lack hydrothecae. One dimension did not agree 

with Watson’s measurements: the length of the 

free adcauline side of the hydrotheca. While 

Watson measured 0.1–0.17 mm, here 0.28–0.31 

mm were found. It seems that new material of 

both species from different localities is needed to 

evaluate their status. 

Distribution 

Eastern Australia, northern Australia, Indonesia, 

Japan, ?New Zealand. Type locality: Off Sydney, 

Australia, 55–64 m. 

Family Halopterididae 

Antennella campanulaformis 

(Mulder & Trebilcock, 1909) 

Fig. 56. 

Plumularia campanulaformis Mulder & Trebilcock, 1909: 

31, pl. 1: figs 6, 9, 10. 

Plumularia campanulaformis var. dubia Mulder & 

Trebilcock 1911: 115, pl. 2: fig. 6. 

Antennella campanuliformis. – Watson 1973: 182, figs 43– 

44. 

Halopteris diaphana. – Millard & Bouillon 1973: 82, fig. 

10L–M. 

Antennella campanulaformis. – Schuchert 1997: 24, fig. 7. 


Kei Islands Expedition, Banda Islands, Kombir, 70–90 m, 6 

Jun 1922, numerous shoots with gonothecae, on sponge and 

presumable polychaete tubes made of sand grains. 

Description 

Colonies erect, shoots thread-like, not branching, 

205 

Fig. 56. Antennella campanulaformis (Mulder & Trebilcock, 

1909). A. Part of stem with main- and intersegment. B. 

Lateral nematothecae and apophysis seen from outer side. C. 

Male gonotheca. D–F. Female gonothecae, same scale as C. 

– Scales: A = 0.1 mm; B = 50 µm; C–F = 0.2 mm. 

lacking hydrocladia, 1–1.5 cm high. Stolons 

creeping, tubular, ramified. Stems heteromerously 

segmented by alternating, distinct, oblique 

nodes and less distinct transverse nodes, 

delimiting main segments bearing a hydrotheca 

and intersegments without hydrotheca. First 

node oblique, in stem region below first node 1– 

3 median nematothecae, sometimes on a separate 

segment flanked by two oblique nodes. Main

206 

segment 0.8 mm long, with central hydrotheca 

and three nematothecae: one median inferior and 

two laterals. Intersegment of variable length, 

0.4–0.6 mm, with a single nematotheca near its 

distal end. 

Hydrotheca cylindrical to campanulate, held 

at an angle of 30–40° to segment axis, length 

abcauline side 0.25–0.27 mm, diameter of opening 

0.20–0.21 mm, margin sinuous, sometimes 

somewhat everted. 

Nematothecae movable. Lateral nematothecae 

on short, rounded apophysis. Nematothecae 

about 50 µm high, egg-shaped, two-chambered, 

upper chamber larger, walls incurved, abcauline 

and adcauline side with round emarginations, 

adcauline notch deeper and broader, reaching 

bottom of upper chamber. Hydranth small, fits 

into hydrotheca, about 16 tentacles. 

Male and female gonothecae present in same 

colony, often on same stem; if so, female gonothecae 

distal to male ones. Female gonotheca 

0.5 mm long, egg-shaped, flattened, end truncated, 

when mature with large convex operculum, 

two nematothecae near base of gonotheca, 

pedicel of gonotheca with one separate segment 

attached to an apophysis originating below hydrothecae. 

Female gonothecae contain one egg 

only. Male gonotheca 0.4 mm, egg-shaped to oblong, 

distal end more pointed, operculum small, 

one nematotheca near base. 

Nematocysts: I, small tentacular capsule, 6 x 2 

µm. – II, microbasic mastigophore in nematophores, 

(16–18) x (5) µm, almond-shaped, discharged 

shaft 0.7 times the capsule length. 

Remarks 

Antennella campanulaformis has recently been 

reported to occur in the north-eastern Atlantic 

(Ansín Agís, Ramil & Vervoort 2001), but Peña 

Cantero & Garcìa Carrascosa (2002) referred this 

population to a new species, Antennella ansini. 

The main character to distinguish A. ansini from 

A. campanulaformis is the occurrence of male 

and female gonothecae on separate stems. 

Distribution 

Australia, Seychelles, Indonesia (new record). 

Depth range 1–90 m. Type locality: Barwon 

Heads, Victoria, Australia. 

P. SCHUCHERT 

Antennella secundaria (Gmelin, 1791) 

Fig. 57. 

Sertularia secundaria Gmelin, 1791: 3856. 

Plumularia secundaria. – Pictet 1893: 53, pl. 2: fig. 26. 

Antennella secundaria. – Billard 1913: 8, fig. 1, pl. 1: figs 1– 

3. – Stechow & Müller 1923: 473. – Mammen 1967: 296, 

fig. 93. – Millard & Bouillon 1973: 77, fig. 10E. – 

Millard 1975: 332, fig. 107F–L. – Vervoort & Vasseur 

1977: 64, fig. 28. – Calder 1997: 29, fig. 7, synonymy. – 

Ryland & Gibbons 1991: 525, fig. 1. – Cornelius 1995b: 

121, fig. 28 A–C, E–G, not D. – Hirohito 1995: 236, fig. 

79a–c. – Schuchert 1997: 14, figs 3–4, synonymy. – 

Watson 1997: 522, fig. 6A–B. – Watson 2000: 45, fig. 

34A–D. – Ansín Agís, Ramil & Vervoort 2001: 140, fig. 

63, bib-liography. 


Kei Islands Expedition stations: 65, male and female gonothecae 

present. – 67, on Diphasia digitalis, no gonothecae. – 

68, on hydroids, no gonothecae. – 71, on sponge and stolons 

of other hydroids, no gonothecae. – 90, on hydroids, with 

female and male gonothecae, two samples. – 104, on 

hydroids, male and female gonothecae present. – 106, on 

hydroids, no gonothecae. – 107, on Bryozoa, no gonothecae. 

– 110, on hydroids, no gonothecae. – 111, only female 

gonothecae present. – Kei Islands Expedition, 5.12°S, 

119.34°W, Ujungpandang, Samalon Island, 35 m, 28 Jun 

1922, on Bivalvia, no gonothecae. – MNHG INVE 25024, 

Bay of Ambon, Moluccas, material of Pictet (1893, as 

Plumularia secundaria), no gonothecae. – MHNG INVE 

32969, Banyuls-sur-Mer, France, Mediterranean, 15 May 

2002, 62 m, on Protula sp., female gonothecae distal to male 

ones, living colony yellow-greenish. 

Description 

Colonies erect, shoots thread-like, lacking hydrocladia, 

mostly unbranched, fertile stems 0.8– 

2 cm high. Stolons tubular, ramified. Basal part 

of stem without hydrothecae, stem above basal 

part heteromerously segmented by alternating 

oblique and transverse nodes. Main segments 

with hydrotheca and four nematothecae: one 

median inferior, two lateral of hydrotheca, and 

one axillary behind hydrotheca. Main segment 

quite short, hydrotheca project beyond transverse 

node. Intersegments mostly with two 

nematothecae, rarely some segments with three, 

length variable within and between stems. 

Hydrotheca cup-shaped, walls in side view 

rather straight, converging towards below, margin 

sinuous, opening forming an angle of 45 to 

55° with the main axis, adcauline side adnate for 

half of its length or less, length of abcauline side 

0.19–0.26 mm, opening diameter 0.20–0.23 mm. 

Nematothecae all two-chambered. Median inferior 

nematothecae with adcauline wall of upper


Fig. 57. Antennella secundaria (Gmelin, 1791); A-D, station 104, colonies having short lateral nematothecae only; E–G, 

colonies with long lateral nematothecae, E & G, station 90, F, station 67. A. Part of stem with main- and intersegment. B. Two 

lateral nematothecae and apophysis, left one seen from inner side, right one in side view. C. Female and male gonothecae. D. 

Basal part of a branched stem. E. Part of stem, main- and intersegment, same scale as A. F. Size variation of lateral 

nematothecae of single stem, same scale as B. G. Gonothecae, same scale as C. – Scales: A, E = 0.1 mm; B, F = 50 µm; C, G 

= 0.2 mm; D = 0.5 mm. 

207

208 

chamber much lowered. Lateral nematothecae 

on long apophysis, conical, walls straight and not 

incurved, adcauline wall of upper chamber lowered, 

sometimes bilabiate; length of laterals very 

variable even within the same stem, usually 0.07 

mm and not reaching beyond hydrothecal rim but 

in Indonesian material frequently longer, sometimes 

up 0.3 mm long. Axillary nematotheca 

rather variably developed, one side reduced. 

Gonothecae of both sexes can occur on the 

same stem, developing below hydrothecae, male 

gonothecae either below female ones, above 

them, or mixed. Female gonotheca 0.6–0.8 mm 

long, diameter 0.4 mm, end truncate with large 

convex lid, pedicel segmented, near bas of gonotheca 

2 nematothecae. Male gonotheca 0.3–0.4 

mm, distal end more rounded and with small 

aperture, at base 1–2 nematothecae. 

Nematocysts: I, small tentacular capsule. II, 

larger mastigophore in nematophores, (16–20) x 

(5.5–7) µm. 

Remarks 

Antennella secundaria is a well known, almost 

cosmopolitan species, and its taxonomy has been 

treated recently by several authors (see synonymy 

list above). 

The study of the specimen here assigned to 

Antennella secundaria, however, brought up 

several problems. While some colonies have 

only short lateral nematothecae as seen in European 

populations (Fig. 57A–B), others have numerous 

very long lateral nematothecae that reach 

far beyond the rim of the hydrotheca (Fig. 57E– 

F). The same stems bearing these extremely long 

nematothecae invariably also have short nematothecae 

and all intermediate lengths. Sometimes 

there is even a long and a short nematotheca 

flanking the same hydrotheca. Such long lateral 

nematothecae have also been observed by Billard 

(1913, Indonesia), Millard (1975, South Africa), 

Rees & Vervoort (1987, Zanzibar). All these 

authors regarded them as variants of one species 

only. Billard (1913) thought that the long nematothecae 

could be regenerated ones. Mammen 

(1967) thought that Billard’s material with long 

nematothecae belonged to a different species and 

he tentatively allocated them to A. allmani Armstrong, 

1879. 

P. SCHUCHERT 

I was unable to find any other significant 

character that co-varied reliably with the presence 

of long lateral nematothecae and thus prefer 

the hypothesis that only one species is present. 

The stems having long nematothecae never 

showed any branching, while those with short 

nematothecae occasionally have branched stems 

(see below). This correlation could, however, be 

purely coincidental. 

The respective position of the male and female 

gonothecae is another problem. In Mediterranean 

(type locality) and South African populations, 

the male gonothecae are below the female 

ones. These observations are based on very 

few observations and it is not clear how variable 

this arrangement is. Watson (2000) found in an 

otherwise typical specimen from northern Australia 

a reversed order. A mixed arrangement was 

reported by Ryland & Gibbons (1991) in material 

from Fiji and by Hirohito (1995, fig. 79c) in a 

Japanese specimen. In the material examined 

here, colonies with short nematothecae had either 

the male gonothecae below the female ones, or 

they were mixed. In one colony having long 

lateral nematothecae the male gonothecae were 

distal to the female ones. It seems thus that at least 

Pacific populations of A. secundaria have a variable 

the arrangement of the male and female 

gonothecae in monoecious stems. 

Some stems examined in this study were 

branched 2–3 times (Fig. 57D). The observed 

branching pattern is characteristic for the genus 

Monostaechas (see Schuchert 1997). Identical 

branched stems have also been described by 

Billard (1913), Millard & Bouillon (1973), 

Watson (1975), Vervoort & Vasseur (1977), 

Ryland & Gibbons (1991), and Calder (1997). 

The “Monostaechas”-like branching seems thus 

to be a characteristic trait of most populations 

of A. secundaria. Billard (1913) noted that the 

branching of A. secundaria and Monostaechas 

are different in that in the latter species a new axis 

is formed by the successive basal stem segments. 

I think this is not really tenable and that there is no 

fundamental difference. This renders Monostaechas 

quadridens (McCrady, 1859) only gradually 

different from A. secundaria. While it is 

absolutely justified to regard M. quadridens as a 

distinct species, the validity of the genus Monostaechas, 

however, is clearly undermined. The


same problem exists for the genus Halopteris and 

a new discussion on generic limits in the family 

Halopterididae is needed. As a further difference 

it was found that the Indonesian specimen had 

mastigophores that are nearly twice as long as 

the ones found in specimens from Europe (cf. 

Schuchert 1997). 

Distribution 

Cosmopolitan species with a distinct preference 

for temperate and tropical waters, occurring from 

the subtidal zone down to 1250 m. Type locality: 

Mediterranean. 

Halopteris plagiocampa (Pictet, 1893) 

Fig. 58. 

Plumularia plagiocampa Pictet, 1893: 56, pl. 3: fig. 50. – 

Billard 1913: 31, fig. 23. – Jäderholm, 1919: 21. 

Halopteris plagiocampa. – Schuchert 1997: 117, fig. 42. – 

Watson 2000: 47, fig. 36A–C. 


MHNG INVE 25021, holotype of Plumularia plagiocampa, 

slide preparation. 


Kei Islands Expedition station 11, infertile, on sponge. – Kei 

Islands Expedition Samalon Island, Ujungpandang, Sulawesi, 

28 Jun 1922, 35 m, infertile, on polychaete tube. 

Description 

Colonies erect, pinnate, hydrocladia in opposite 

pairs, stems 1–2 cm high. Stem monosiphonic, 

straight, unbranched, with basal part devoid of 

hydrothecae and hydrocladia and a longer distal 

part. This distal part homomerously segmented 

by transverse nodes, in terminal region sometimes 

heteromerously segmented through an oblique 

node below hydrotheca. Each cauline segment 

with a hydrotheca at its distal end, hydrotheca 

flanked by two opposite apophyses for 

the hydrocladia; three nematothecae in association 

with the hydrotheca: two lateral and one 

median inferior; below cauline hydrotheca on the 

fused intersegment 3–4 median nematothecae. 

Up to 16 hydrocladia per side. Apophysis 

followed by a short, quadrangular segment, both 

lacking a nematotheca. Remaining part of hydrocladium 

heteromerously segmented by alternating 

oblique and transverse nodes, often with 

a quadrangular segment without nematothecae 

209 

Fig. 58. Halopteris plagiocampa (Pictet, 1893); station 11. 

A. Stem segment and proximal parts of hydrocladia. B. 

Repeated unit of hydrocladium (main- and intersegment). C. 

Lateral nematotheca seen from inner side. – Scales: A = 0.2 

mm; B = 0.1 mm; C = 50 µm. 

intercalating between main- and intersegments. 

Intersegments proximal to main segment, with a 

single median nematotheca. Main segments with 

three nematothecae: one median inferior and a 

pair of laterals. 

Hydrotheca cup-shaped, placed in middle of 

main segment, margin reaches to distal end of 

segment, rear- and frontal wall quite straight and 

roughly parallel in side view. Hydrotheca adnate 

for about half its length, rim smooth and flat, 

opening forming an angle of about 40 to 50° with 

hydrocladial axis. Depth of hydrotheca 0.12 mm, 

diameter 0.15 mm. 

Nematothecae of stem and hydrocladia all 

two-chambered and movable. Median inferior 

nematotheca of main segments conical, adcauline 

wall of upper chamber lowered. Lateral nematothecae 

on very short pedicel or pedicel lacking, 

conical, walls straight, rim deeply emarginated 

on inner side. Nematothecae of inter-

210 

segments similar to median inferior but with 

longer lower chamber. 

Gonothecae absent in present material, see 

Schuchert (1997) for a description and figures. 

Remarks 

The type material of Halopteris plagiocampa 

(Pictet, 1893) was recently located (see Schuchert 

1997) and was re-examined for this study. 

The new material from the Kei Islands Expedition 

was indistinguishable from the type material. 

My previous description of the stem segmentation 

(Schuchert 1997) is not entirely correct. 

Nearly the whole stem is segmented by transverse 

nodes only, except for the most distal part 

where an oblique node below the hydrotheca can 

delimit an intersegment. In the homomerously 

segmented part of the stem, the intersegments are 

thus fused to the lower end of the main segments. 

Contrary to the previously examined material, 

the lateral nematothecae in the present material 

and the type specimen had deep emarginations 

on the adcauline side. Such a variation, however, 

is quite usual in this family. 

Distribution 

Indonesia, Japan, northern Australia. Type locality: 

Bay of Ambon, Moluccas, Indonesia, zone of 

corals (Pictet 1893). 

Family Plumulariidae 

Plumularia badia Kirchenpauer, 1876 

Fig. 59. 

Plumularia badia Kirchenpauer, 1876: 34, 45, pl. 1: figs 3– 

4, pl. 4: fig. 3. – Bale 1884: 128, pl. 18: figs 1–2. – 

Stechow & Müller 1923: 473. – Vervoort 1941: 221. – 

Watson 2000: 51, fig. 39A–E. 

Plumularia ramsayi Bale, 1884: 131, pl. 11: figs 3–4. – 

Billard 1913: 52. – Vervoort 1941: 221. 

Plumularia gracilis von Lendenfeld, 1885: 476, pl. 14: fig. 

17, pl. 17: figs 28–29. 


Kei Islands Expedition stations: 71, several stems, without 

gonothecae. – 104, with gonothecae. – Kei Islands Expedition, 

Samalon Island near Ujungpandang, Sulawesi, 35 m, 

28 Jun 1922, with gonothecae, on shell fragment. 

P. SCHUCHERT 

Fig. 59. Plumularia badia Kirchenpauer, 1876; A–B station 

71; D station 104. A. Part of colony. B. Branch with apophysis 

and part of hydrocladium. C. Internode of hydrocladium. 

D. Gonotheca, perhaps not fully grown yet, same 

scale as B. – Scales: A = 1 cm; B = 0.1 mm; C = 50 µm. 

Description 

Colonies up to 8 cm high, multi-pinnate, stems 

monosiphonic, stiff, branches opposite or alternate, 

in one plane. Stem and branches bear alternate 

hydrocladia. Stem and branches without 

nodes, without hydrothecae, with long apophyses 

for hydrocladia (0.18 mm). Three nematothecae 

associated with each apophysis: two on 

apophysis, one close to base. 

Hydrocladia relatively short and very thin, all 

in plane of branches and stem, length quite uniform, 

with up to 10 hydrothecae, homomerously


segmented by oblique nodes, segments about 0.3 

mm long, all segments with a hydrotheca and 

three nematothecae: one below and two lateral to 

hydrotheca. Internode with internal ribs, variably 

developed: one at each end, one below median 

nematotheca, one at base of hydrotheca. 

Hydrotheca cup-shaped, depth 64–80 µm, 

placed centrally on internode, adcauline side 

adnate, abcauline wall at an angle of about 30° to 

internode axis, straight or with slight curvature, 

hydrothecal margin sinuate, distinctly lowered 

towards internode. 

All nematothecae two-chambered and movable, 

conical, walls straight, rim not incurved, 

adcauline wall of upper chamber emarginated. 

Median inferior nematotheca not reaching to hydrotheca, 

on prominence of internode. Lateral 

nematothecae almost as big as depth of hydrotheca. 

Gonothecae inserted without pedicel in upper 

axil of apophyses, small (0.2 mm), conical, distally 

truncated, terminal orifice oval, perisarc 

thin. 

Colour: Stem and branches deep brown, hydrocladia 

white. 

Distribution 

Indonesia, tropical and subtropical coast of Australia 

(Watson 2000). Type localities: Brisbane 

and Singapore. 

Plumularia habereri Stechow, 1909 

Fig. 60 

Plumularia habereri Stechow, 1909: 77, pl. 6: fig. 4. – 

Stechow 1913: 91, figs 59–60. – van Gemerden-Hoogeeven 

1965: 60, figs 34–36. – Ryland & Gibbons 1991: 

532: fig. 5. 

Plumularia habereri var. attenuata Billard, 1913: 42, fig. 

34. 

Plumularia habereri var. elongta Billard, 1913: 44, figs 35– 

37. 

Plumularia habereri var. subarmata Billard, 1913: 45, fig. 

38. 

Plumularia habereri var. mediolineata Billard, 1913: 45, 

fig. 39, pl. 3: fig. 31. 

Plumularia habereri var. mucronata Billard, 1913: 46, fig. 

40, pl. 2: fig. 24. 

Dentitheca habereri. – Hirohito 1995: 259, fig. 87a–c. 


Kei Islands Expedition, Waling, Banda Islands, 10 m, 15 Jun 

1922, fragmented plume with gonothecae. – Kei Islands 

211 

Fig. 60. Plumularia habereri Stechow, 1909; A–D, Banda 

Islands; E, Samalon Island. A. Colony silhouette (damaged). 

B. Part of branch with apophysis. C. Branch with gonotheca, 

same scale as B. D. Two hydrothecae from same hydrocladium; 

note variability. E. Hydrocladial internode of juvenile 

colony, same scale as D. – Scales: A = 2 cm; B, C = 0.2 

mm; D, E = 0.1 mm. 

Expedition, Samalon Island near Ujungpandang, Sulawesi, 

35 m, 28 Jun 1922, juvenile colony, together with P. badia. 

Description 

Colonies 5–25 cm high, multi-pinnate, up to

212 

fourth order branching, roughly in one plane, 

stem and branches polysiphonic, thinning to 

monosiphonic in distal regions. Stem and 

branches in polysiphonic parts composed of an 

embedded main tube and auxiliary tubes. Main 

tube originally with alternate hydrocladia, but 

these often broken off in older parts. Branches 

originating from auxiliary tubes, auxiliary tubes 

bearing nematothecae. Stem and branches without 

nodes in large colonies, homomerously segmented 

in juveniles, with alternate apophyses for 

hydrocladia, without hydrothecae. In segmented 

stems two hydrocladia per internode. Two nematothecae 

associated with each apophysis, additional 

nematothecae present on stem and 

branches. 

Hydrocladia with up to 15 hydrothecae, nodes 

either mostly absent or homomerously segmented 

by transverse nodes, each hydrotheca and 

associated with three nematothecae: one below 

and two lateral to hydrotheca. Hydrocladium often 

with numerous, evenly spaced, thick internal 

ribs formed by annular thickenings, some regions 

with no or only weakly developed ribs. 

Hydrotheca tubular, abcauline wall 0.25–0.3 

mm, straight and parallel to hydrocladial axis, 

adcauline side completely adnate, shorter than 

abcauline side, margin therefore much lowered 

on adcauline side, lateral rim with two broad and 

shallow lobes, on inside of abcauline wall frequently 

a transverse semicircular perisarc thickening, 

rim on adcauline side with thickened perisarc. 



adcauline wall of upper chamber emarginated, 

lower chamber longer than upper one. Median 

inferior nematotheca far below hydrotheca, not 

reaching hydrotheca, on distinct prominence of 

internode. Lateral nematothecae inserted near 

rim of hydrotheca, about 70 µm high. 

Female gonotheca inserted in upper axil of 

apophyses, 0.3 high mm, top-shaped (turbinate), 

end flat, wall straight, no pedicel. Male gonothecae 

not seen 

Remarks 

The Indonesian population of Plumularia habereri 

is very variable and Billard (1913) proposed 

P. SCHUCHERT 

a number of nominal variants. Because they are 

sympatric, these variants are not subspecies, but 

represent phenotypic or genotypic variability. 

Most of them are quite unlike the form from the 

original location in Japan (Stechow 1909, Hirohito 

1995), from the Caribbean (van Gemerden- 

Hogeveen 1965), or from Fiji (Ryland & Gibbons 

1991). The material examined here clearly 

matched Plumularia habereri var. mediolineata 

Billard, 1913 as most hydrothecae had an internal 

perisarc thickening (Fig. 60D). Some hydrothecae 

of the same stem or even hydrocladium, 

however, lacked this thickening and more approached 

the variant elongata. The more juvenile 

colony also corresponded to the form elongata 

(Fig. 60E). Only few specimens of all these variants 

are known and more material is needed to 

further evaluate the validity of all of them. Some, 

especially the form described above, could prove 

to be separate species. 

Distribution 

Japan, Indonesia, Caribbean Sea. Type locality: 

Between Ito and Hatsushima Islands, Sagami 

Bay, Japan. 

Plumularia scabra Lamarck, 1816 

Fig. 61. 

Plumularia scabra Lamarck, 1816; 127. – Billard 1907: 322. 

– Billard 1913: 47. – Watson 2000: 52, fig. 40A–E. 

Plumularia effusa Busk, 1852: 400. – Kirchenpauer 1876: 

46, pl. 1: fig. 4, pl. 5: fig. 4. – Bale 1884: 129, pl. 18: fig. 

5. 

Acanthella effusa. – Allman 1883: 27, pl. 6: figs 1–4. – von 

Campenhausen 1896b: 315. – Stechow & Müller 1923: 

474. 



large cluster of 25 cm high stems. – 106, with gonothecae. – 

107. 

Description 

Colonies 5–25 cm high, comprising many stems, 

multi-pinnate, up to third-order branching, sidebranches 

in verticels and not in one plane, stem 

and branches monosiphonic, quite rigid, all bearing 

alternate hydrocladia, hydrocladia in older 

parts usually lost, branches of lower part of stem 

usually broken off. Stem and branches without 

nodes, with long apophyses for hydrocladia (0.12


Fig. 61. Plumularia scabra (Lamarck, 1816); A, station 72; 

B–D, station 106. A. Colony silhouette, height 13 cm. B. Part 

of hydrocaulus (branch) with apophysis, scale bar 0.1 mm. 

C. Segment of hydrocladium. D. Gonothecae. – Scales: B = 

0.1 mm; C = 50 µm; D = 0.2 mm. 

213 

mm), only in most distal portions with oblique 

nodes, each segment with two apophyses, without 

hydrothecae. Two to three nematothecae associated 

with each apophysis: one or two on 

apophysis, one close to base. 

Hydrocladia with up to 15 hydrothecae, homomerously 

segmented by oblique nodes, segments 

about 0.25 mm long, all segments with 

hydrotheca and three nematothecae: one below 

and two lateral to hydrotheca. Internode with 

internal ribs, variably developed: one at each 

end, one at rear wall of hydrotheca, one curved 

between hydrotheca and median inferior nematotheca. 

Several terminal hydrocladia of some 

branches often replaced by thorn-like growth of 

the apophysis bearing a nematotheca. 

Hydrotheca cup-shaped, depth 0.13 mm, centrally 

placed on internode, adcauline side adnate, 

abcauline wall strongly S-shaped, adcauline wall 

convex, hydrothecal margin with two broad, 

rounded lateral lobes. 



adcauline wall of upper chamber emarginated, 

lower chamber longer than upper one. Median 

inferior nematotheca immediately below hydrotheca, 

reaching beyond middle of hydrotheca, 

not on distinct prominence of internode. Lateral 

nematothecae inserted near rim of hydrotheca, 

about 70 µm high. 

Gonotheca inserted in upper axil of apophyses, 

0.5 mm, ovoid, flattened, distal end truncated 

and oblique, orifice slit-like. 

Remarks 

See under Polyplumaria cornuta. 

Distribution 

Northern Australia, Singapore, Philippines, Indonesia. 

Type locality: “South Seas” (Lamarck, 

1816). 

Polyplumaria cornuta (Bale, 1884) 

Fig. 62. 

Plumularia cornuta Bale, 1884: 132, pl. 11: figs 1–2. 

Polyplumaria cornuta. – Billard 1913: 53, figs 65–66, pl. 3: 

fig. 33, pl. 4: 35–36. – Watson 2000: 56, fig. 44A–F. 

Polyplumaria cornuta var. longispina Billard, 1913: 56, fig. 

67.

214 



with long hydrocladia. – 65. – 66. – 67, with gonothecae. – 

69. – 72. – 83. – 90. – 102. – 103. – 112. 

Description 

Colonies forming solitary stems, stems very slender 

and limp, monosiphonic, reaching heights of 

20 cm and more, branched, multi-pinnate, stems 

with relatively short branches, these branches not 

branched again, thus branching order being first 

degree only, branches arranged helically around 

stem in upper half. Stem with hydrocladia, either 

P. SCHUCHERT 

Fig 62. Polyplumaria cornuta (Bale, 1884); A, station 66; B–D, station 72; E, station 53. A. Colony silhouette. B. Oblique view 

of apophysis, base of hydrocladium and modified secondary hydrocladium, circle on apophysis is scar from broken-off 

gonotheca. C. Modified secondary hydrocladium with additional hydrothecate segment at end, same scale as B. D. 

Hydrocladial internode in side view. E. Gonotheca. – Scales: A = 1 cm; B, C = 0.1 mm; D = 50 µm; E = 0.2 mm. 

in two lateral rows or in verticels, often broken 

off. Stolons root-like, anchored in mobile substrata. 

Terminal apophyses never modified into 

thorn-like process. 

Hydrocladia on branches in two rows, origin 

shifted to upper side, with up to 10 hydrothecae, 

homomerously segmented by oblique nodes, 

segments about 0.2 mm long, all segments with 

hydrotheca and three nematothecae: one below 

and two lateral to hydrotheca. Proximal part of 

hydrocladium often strongly modified, fused to 

apophysis, bifurcated, one normal hydrocladium 

and one branch with a basal hydrotheca and then


tapering into pointed horn-like process with a 

nematotheca, sometimes on top of this secondary 

hydrocladium an additional terminal segment 

bearing a hydrotheca and nematothecae (Fig. 

62C). 

Internodes with internal ribs, variably developed: 

one at each end, two at rear wall of hydrotheca, 

one curved between hydrotheca and 

median inferior nematotheca. 

Hydrotheca cup-shaped, depth 0.13 mm, centrally 

placed on internode, adcauline side adnate, 

abcauline wall weakly s-shaped, adcauline wall 

straight, hydrothecal margin with two broad, 

rounded lateral lobes. 



adcauline wall of upper chamber lowered, lower 

chamber longer than upper one. Median inferior 

nematotheca immediately below hydrotheca, 

reaching beyond middle of hydrotheca, sometimes 

on indistinct prominence of internode. Lateral 

nematothecae inserted near rim of hydrotheca, 

about 80 µm high. 

Gonotheca inserted in upper axil of apophyses, 

0.45 mm, diameter 0.3 mm, conical, walls 

quite straight, distal end planar, circular. 

Remarks 

If present, the characteristically modified secondary 

hydrocladium (Fig. 62B) renders Polyplumaria 

cornuta (Bale, 1884) easy to recognize. 

Unfortunately, these horn-like processes can be 

quite rare and some younger colonies may lack 

them entirely. Because the microscopic structure 

of the hydrocladia of Polyplumaria cornuta and 

Plumularia scabra are virtually indistinguishable 

(cf. Figs 61C and 62D), other characteristics 

Table 1. Differences between Polyplumaria cornuta and Plumularia scabra. 

215 

must be used to identify such material. The important 

differences are summarized in Table 1. 

The easiest way to distinguish them is by comparing 

the colony form. While P. scabra has 

colonies comprising usually several stems that 

are branched up to the third order, P. cornuta 

colonies form very elongate, solitary stems with 

simple, short branches. The hydrocladia are also 

generally shorter, but the length is quite variable 

(cf. Figs 61A and 62A). The longest hydrocladia 

were observed in a sample from deeper waters 

(250 m). This sample also regularly had secondary 

hydrocladia, while in colonies with shorter 

hydrocladia they can be scarce or absent. 

The hydrocladia of the stem of Polyplumaria 

cornuta can be arranged in verticels and the 

coenosarc of the stem can be canaliculated, both 

characteristic for the genus Nemertesia, a fact 

already noted by Billard (1913). The limits of the 

genera Plumularia, Polyplumaria and Nemertesia 

are thus somewhat diffuse. 

Distribution 

Indonesia, tropical coasts of Australia. Type locality: 

Holborn Island, Queensland, Australia. 

Nemertesia indivisa (Allman, 1883) 

Fig. 63. 

Sciurella indivisa Allman, 1883: 26, pl. 5: figs 1–4. – 

Kirkpatrick 1890: 609. 

Antennularia cylindricala Bale, 1884: 146, pl. 10: fig. 7. 

Nemertesia indivisa. – Billard 1910: 38. – Billard 1913: 60, 

fig. 50. 


Kei Islands Expedition stations: 67. – 71. – Kei Islands 

Expedition, Samalon Island, Ujungpandang, Sulawesi, 25 

m, 29 Jun 1922. 

Character Polyplumaria cornuta Plumularia scabra 

Hydrocladia may be branched, secondary branch modified never branched 

Terminal apophyses never modified some drawn into horn-like process 

Branching (exclusive hydrocladia) 1st order up to 3rd order 

Stem soft stiff 

Hydrocladia on stem two rows or in verticels two rows 

Hydrocladia often recurved towards branch end mostly straight 

Gonotheca conical, circular cross-section ovoid, flattened, distal end truncated 

Hydrotheca, abcauline wall shallow double-curvature strong double-curvature

216 

Fig. 63. Nemertesia indivisa (Allman, 1883); Samalon 

Island. A. Colony silhouette. B. One stem internode seen 

from above, showing arrangement of hydrocladia in four 

lateral rows. C. Hydrocladial segment. D. Lateral nematotheca. 

– Scales: A = 2 cm; B = 0.5 mm; C = 0.1 mm; D = 50 

µm. 

Description 

Colonies with several unbranched or occasionally 

branched stems, 5–15 cm high, stems clustered, 

with laterally held hydrocladia all along 

most of the stem length giving impression of 

stems being pinnate. Stems thick, usually with 

distinct nodes but nodes may be indistinct in 

some regions, majority of internodes with four 

hydrocladia, less frequently two, six, or more. 

Hydrocladia originating on relatively short apophyses, 

each apophysis associated with up to four 

nematothecae and 1–2 or more close to apophysis. 

Coenosarc of stem canaliculated. 

Hydrocladia short in comparison to stem 

length, in four longitudinal rows but directed 

P. SCHUCHERT 

towards sides, in opposite pairs. Basal parts of 

younger stems may have only two lateral rows of 

hydrocladia, being thus truly pinnate, in distal 

parts the hydrocladia can be arranged around 

the stem in whorls comprising three hydrocladia 

each. Hydrocladia homomerously segmented by 

slightly oblique nodes, internodes quite short 

(0.4–0.5 mm), each with one hydrotheca and 

three nematothecae: one median inferior, tow 

laterals. Internal ribs absent. Median inferior 

nematotheca on slight elevation or not so. 

Hydrotheca cylindrical, depth 0.2–0.26 mm, 

diameter about 0.1 mm, adcauline wall completely 

adnate, adcauline and abcauline wall 

quite straight and nearly parallel, opening-plane 

perpendicular to internode axis, rim somewhat 

lowered on adcauline side. 

Lateral nematothecae 60 µm high, close to 

hydrothecal margin, ovoid to conical, upper and 

lower chamber nearly of same height, wall of 

upper chamber slightly incurved, rim emarginated 

on outer and inner side, emarginations 

on inner side much deeper, reaching bottom of 

upper chamber. Median inferior nematothecae 

longer, conical, rim not incurved, rim lowered on 

adcauline side only. 

Gonothecae not observed, according to Billard 

(1913) about 1 mm, irregularly lobed, flattened, 

with numerous nematothecae. 

Remarks 

The arrangement of the hydrocladia of Nemertesia 

indivisa (Allman, 1883) shows quite some 

variation. The majority of them are in four longitudinal 

rows and they are directed sideways. But 

also truly pinnate sections and sections with verticillate 

arrangement occur. Nemertesia indivisa 

with its mostly laterally held hydrocladia, the 

deep hydrothecae, and the lobed gonothecae furnished 

with nematothecae is somewhat unusual 

among it congeners. The peculiar gonotheca induced 

Allman (1883) to place this species in the 

new genus Sciurella, which has, however, not 

found general acceptance. 

Distribution 

Northern Australia, Indonesia. Type locality: 

Somerset Island, Cape York, Torres Strait, Australia, 

9–18 m.


Sibogella erecta Billard, 1911 

Fig. 64. 

Sibogella erecta Billard, 1911a: 108. – Billard 1913: 61, fig. 

51, pl. 3: fig. 32. – Billard 1929b: 72. – Vervoort 1941: 

222. – Hirohito 1969: 27, fig. 18. – Hirohito 1995: 282, 

fig. 97g. 

Stechowia armata Nutting, 1927: 230, pl. 44: figs 1–2. 


Kei Islands Expedition station 18. 

Description 

Colony comprising several erect stems, up to 

10 cm high. Stem monosiphonic, composed 

of a trunk with spirally arranged side-branches, 

branches bearing hydrocladia. Main stems unsegmented, 

with numerous nematothecae in 

three rows. Side-branches homomerously segmented 

by transverse nodes, segments without 

hydrotheca, with a subterminal apophysis for 

hydrocladium, apophysis with a nematotheca 

and a mamelon, in middle of segment a further 

nematotheca. 

Hydrocladia alternate, segmented by transverse 

nodes, only one hydrotheca per hydrocladium, 

distal part modified into flexible process. 

First segment of hydrocladium simple (intersegment), 

with one nematotheca. Second segment 

long, bearing at distal end hydrotheca and 

three nematothecae: one median inferior far below 

hydrotheca, two laterals near margin of hydrotheca. 

Distal to hydrothecate segment several 

simple segments, each with one or two nematothecae 

thin, jointed flexibly and forming a tendril-like 

appendage. 

Hydrotheca cup-shaped, shallow, abcauline 

side 50 µm, diameter 70 µm, adcauline side 

adnate, rim even. 

Nematothecae all movable and two-chambered, 

conical, lower chamber longer than upper 

chamber, wall of upper chamber lower on one 

side. 

Gonothecae not observed, according to Billard 

(1913) pyriform, 0.3–0.34 mm long, in upper 

axil of apophyses of hydrocladia 

Remarks 

The flexible, modified distal hydrocladia with 

up to 12 segments (Billard 1913) make this species 

quite unique and immediately recognizable. 

It would be interesting to learn more about 

217 

Fig. 64. Sibogella erecta Billard, 1911. A. Colony silhouette. 

B. Part of side-branch with one hydrocladium. – Scales: 

A = 2 cm; B = 0.1 mm. 

its function, which is presumably defensive. Billard 

(1927) described the arrangement of sidebranches 

as in three longitudinal rows. In the 

present material, this arrangement is better described 

as spiral. Occasionally it is also pinnate.

218 

Distribution 

Indonesia, Philippines, Japan. Type locality: Indonesia, 

1°42.5’S, 130°47.5’E, 32 m. 

Family Aglaopheniidae 

Gymnangium longicorne (Busk, 1852) 

Fig. 65. 

Plumularia longicornis Busk, 1852: 399. 

Aglaophenia longicornis. – Bale 1884: 157, pl. 14: figs 7–8, 

pl. 17: fig. 5. 

Lytocarpus longicornis. – Allman 1883: 45, pl. 19: figs 4–6. 

Macrorhynchia (?) longicornis. – Stechow & Müller 1923: 

474. 

Halicornaria longicornis var. sibogae Billard, 1913: 67, fig. 

54, pl. 4: fig. 38. 

Halicornaria intermedia Billard, 1913: 65, fig. 53, pl. 4: fig. 

37. 

Gymnangium longicorne. – Watson 2000: 60, fig. 48A–F. 


Kei Islands Expedition stations: 67. – 68, 30 m and 50 m 

depth. – 71. – 73, with gonothecae. – 104. 

Description 

Colonies up to 20 cm high, multi-pinnate, 

branching in one plane; composed of a polysiphonic 

main trunk and pinnately arranged sidebranches 

bearing themselves pinnately arranged 

hydrocladia. Main trunk either unbranched or 

forked, strongly polysiphonic up to distal end, 

composed of a superficial primary tube and numerous 

auxiliary tubes. Primary tube with alternate 

hydrocladia, these short (2–3 hydrothecae) 

and often lost. No nematothecae on auxiliary 

tubes. From auxiliary tubes of main trunk issue 

pinnately arranged side-branches, these always 

monosiphonic, 1.5–2 cm long, at base a deeply 

cut, oblique hinge-joint rendering branch easily 

movable, other nodes only visible in more distal 

parts, each internode with an apophysis bearing a 

hydrocladium. Below hinge-joint no hydrocladia, 

only median nematothecae. Apophysis of 

hydrocladia associated with two nematothecae, 

one on abcauline end and one in upper axil, both 

nematothecae with two apertures, one aperture 

much larger than the other. 

Hydrocladia thin and dense, curved, not in one 

plane, planes forming an angle < 90°, hydrothecae 

facing towards above, hydrocladia relatively 

short, with up to 7 hydrothecae, with dis- 

P. SCHUCHERT 

tinct oblique nodes, internode length about 0.2 

mm. Each segment with two well developed 

internal ribs. 

First or second hydrocladium of side-branch 

often modified into long, very flexible pseudophylactocarp; 

proximal 2–5 segments like in 

normal hydrocladia, then up to 12 modified segments 

with without hydrotheca but with three 

long nematothecae. 

Hydrotheca about 0.22 mm in total length, 1/5 

of its upper end curved for nearly 90°, lower part 

straight or slightly curved, slightly inclined towards 

above, adcauline side adnate for ¾ of its 

length, opening-plane tilted towards above or 

parallel to internode axis, margin with two broad, 

rounded cusps, one on each lateral side and one 

frontal, the latter cusp shallow and appearing as 

frontal tooth in side view. Distal part of abcauline 

hydrothecal wall sharply bent, at site of bend 

an abcauline perisarc thickening projecting into 

hydrotheca, on adcauline side near base of hydrothecae 

a second, horizontal intrathecal ridge, 

length and thickness very variable, opening for 

hydranth below this ridge, axis of extended 

hydranth thus S-shaped within hydrotheca. Hydranth 

with about 10 tentacles. 

Median inferior nematotheca tubular, distal 

end sometimes slightly swollen, mostly very 

long, as long or longer as height of hydrotheca, 

the first hydrothecae of a hydrocladium may 

have much shorter median nematothecae. Median 

nematotheca adnate up to the middle of the 

hydrotheca, with three openings: one at distal 

end, one on upper side where becoming free from 

hydrotheca, and one leading into the lumen of the 

hydrotheca. Lateral nematothecae thin and tubular, 

straight, following free upper wall of hydrotheca, 

reaching beyond margin of hydrotheca. 

Gonothecae on upper axil of apophyses for 

hydrocladia, 0.4 mm long, leaf-shaped, flattened, 

rounded distal end without opening, aperture on 

side, slit-like, short pedicel near base. 

Remarks 

With its feather-like side-branches, pivoting at 

the slightest movement, the long nematothecae, 

and the lash-like modified hydrocladia, Gymnangium 

longicorne (Busk, 1852) is a very characteristic 

species. The very flexible hinge joint


Fig. 65. Gymnangium longicorne (Busk, 1852); A, station 71; B–E, station 68; F, station 73. A. Colony silhouette. B. Part of 

sidebranch with apophysis (pointing towards right) and two nematothecae. C. Hydrocladial segment with common form of 

long median nematotheca. D. Segment of proximal region of hydrocladium with less common, short median nematotheca, 

same scale as C. E. Modified hydrocladium (pseudophylactocarp). F. Gonotheca, same scale as B. – Scales: A = 1 cm; B, F = 

0.1 mm; C–D = 50 µm; E = 0.2 mm. 

of the side-branches, well described by Allman 

(1883), renders the side-branches very movable. 

The modified hydrocladia, named pseudophy- 

219 

lactocarps by Watson (2000), are normally regularly 

present, but some colonies have only few of 

them. Watson (2000) argued that these structures

220 

are not homologous to phylactocarps because 

they neither bear gonothecae nor protect them. 

The correlation of the occurrence of these pseudophylactocarps 

and absence of epibionts led 

Watson (2000) assume that they have a defensive 

function. 

Halicornaria intermedia Billard, 1913 was 

regarded by Rees & Vervoort (1987) as a synonym 

of G. eximium (Allman, 1874). I agree with 

Watson (2000), that Halicornaria intermedia 

more probably belongs to Gymnangium longicorne. 

Billard (1913) mentioned that the type 

colony of H. intermedia has modified hydrocladia 

(pseudophylactocarps), a structure not 

known to occur in G. eximium. 

Rees & Vervoort (1987) regarded the record 

of Allman (1883) of L. longicornis as a misidentification 

and referred it to G. eximium. Allman’s 

material had monosiphonic side-branches 

with hinge-joints and the median inferior nematothecae 

were very long. Allman’s figure of the 

colony (1883, pl. 19: fig. 4) is also very characteristic. 

Although Allman did not mention modified 

hydrocladia, his identification seems correct 

beyond any doubt. Gymnangium eximium can be 

distinguished from G. longicornis by the shorter 

median inferior nematotheca, the polysiphonic 

side-branches without hinge-joint, and absence 

of modified hydrocladia (based on the description 

by Rees & Vervoort 1987). 

Distribution 

Tropical Australia, Indonesia, Philippines. Type 

locality: Prince of Wales Channel, Torres Strait, 

Australia. 

Gymnangium cf. gracilicaule (Jäderholm, 

1903) 

Fig. 66. 

Lytocarpus gracilicaulis Jäderholm, 1903: 299, pl. 14: figs 

3–4. 

Halicornaria gracilicaulis. – Billard 1913: 63. – Billard 

1933: 25, pl. fig. 5. – Vervoort 1967: 47, figs 14–15. 

?Halicornaria gracilicaulis var. armata Billard, 1913: 65, 

fig. 52. 

Halicetta gracicaulis. – Hirohito 1995: 293, fig. 103b–d. 

Gymnangium gracilicaule gracilicaule Millard, 1968: 282. 

– Millard 1975: 443, fig. 136A & D. 

Gymnangium gracilicaule. – Rees & Vervoort 1987: 168, 

fig. 40, synonymy. – Watson, 1997: 539, fig. 8G–H. 

Lytocarpus philippinus. – Rho 1969: 165, figs 5–6, pl. 1: fig. 

6, pl. 2: fig. 8. 

P. SCHUCHERT 

Fig. 66. Gymnangium cf. gracilicaule (Jäderholm, 1903). A. 

Silhouette of damaged colony, lower part of main trunk 

overgrown with other organisms. B. Side view of sidebranch 

segment with apophysis and two nematothecae. C. 

Hydrocladial segment. – Scales: A = 1 cm; B = 0.1 mm; C = 

50 µm. 


Kei Islands Expedition station 107, no gonothecae. 

Description 

Colonies up to 6 cm high, multi-pinnate, branching 

in one plane; composed of a polysiphonic 

main trunk and pinnately arranged lateral 

branches bearing themselves pinnately arranged 

hydrocladia. Main stem weakly polysiphonic up 

to distal end, composed of a superficial primary 

tube and 2–3 auxiliary tubes bearing side-


branches, no nematothecae on auxiliary tubes. 

Primary tube with alternate hydrocladia. Sidebranches 

always monosiphonic, about 1.5 cm 

long, at base a deeply cut, oblique hinge-joint 

rendering branch very movable, other nodes only 

visible in more distal parts, each internode with 

an apophysis bearing a hydrocladium. Below 

hinge-joint no hydrocladia, only median nematothecae. 

Apophysis of hydrocladia associated 

with two nematothecae, one on abcauline end 

and one in upper axil, both nematothecae with 

two apertures. 

Hydrocladia alternate, curved, relatively 

short, with up to 7 hydrothecae, with distinct 

nodes, internode length about 0.25 mm. Each 

segment with two internal ribs, not much developed. 

Hydrotheca about 0.25 mm in total length, 

distal third curved for nearly 90°, lower 2/3 

straight and inclined towards hydrocladial axis, 

adcauline side adnate for ¾ of its length, opening 

tilted slightly towards above, margin smooth, 

without lateral cusps or median tooth, distal part 

of abcauline wall sharply bent, at site of bend an 

abcauline perisarc thickening projecting into 

hydrotheca. On adcauline side near base of hydrothecae 

a second, horizontal intrathecal ridge, 

length and thickness very variable. 

Median inferior nematotheca tubular, not 

longer than about 2/3 the depth of the hydrotheca, 

end reaching to level of upper curvature of 

hydrotheca, with three openings: one at distal 

end, one on upper side where becoming free from 

hydrotheca, and one leading into the lumen of the 

hydrotheca. Lateral nematothecae thin and tubular, 

straight, following free upper wall of 

hydrotheca, reaching beyond margin of hydrotheca. 

Gonothecae not observed, according to Vervoort 

(1967) horn-shaped, 0.4–0.45 mm long, 

end truncated, flattened, aperture slit-like, females 

with one egg only. 

Remarks 

The present Indonesian material was only hesitatingly 

assigned to Gymnangium gracilicaule 

because it does not agree entirely with the description 

of the type material given by Rees & 

Vervoort (1987): the abcauline wall is not curved 

221 

but rather bent, the total length of the hydrotheca 

is smaller (0.25 versus 0.29–38 mm), and the 

abcauline wall of the hydrotheca at the curvature 

is quite thickened and forms a short septum projecting 

into the hydrotheca. Such a thickening is 

also known from G. eximium and it can be very 

variably expressed (Rees & Vervoort 1987). Although 

the observed variations are within the 

variation observed for other similar hydroids, it is 

nevertheless possible that the present material 

belongs to another species. 

Gymnangium gracilicaule and Gymnangium 

eximium (Allman, 1874) resemble each other and 

need careful examination to be distinguished. 

Rees & Vervoort (1987) re-examined the type 

material of G. graciliaule and worked out the 

differences to G. eximium. The latter species 

differs from G. graciliaule: in having polysiphonic 

side-branches instead of strictly monosiphonic 

ones, its hydrotheca is less sinuous and 

has a margin with lateral lobes, the axillary 

nematotheca above the cauline apophysis has 

one aperture. Very likely correlated with the 

polysiphonic side-branches, the strong, oblique 

hinge joint found in G. graciliaule is apparently 

absent in G. eximium. 

The likewise similar G. longicorne (see 

above) has much denser hydrocladia (two times), 

thicker stems, the median inferior nematothecae 

are usually longer, the hydrothecal margin is 

distinctly lobed, and modified hydrocladia are 

usually present (cf. Figs 65 and 66). Comparing 

colonies of both species side by side, the differing 

habits are very evident (cf. Fig. 65A and 66A), 

but it could be that it is only an extreme variant of 

G. longicorne. 

Distribution 

Japan, Indonesia, Indian Ocean, South Africa, 

Red Sea, Western Australia. Type locality: 

Southern Japan, 90 m. 

Macrorhynchia philippina Kirchenpauer, 

1872 

Fig. 67. 

Macrorhynchia philippina Kirchenpauer, 1872: 19. – Stechow 

& Müller 1923: 475. – ?Not Hirohito 1983: 78, fig. 

41. – ?Not Rees & Vervoort 1987: 177, fig. 43. – Ryland 

& Gibbons 1991: 553, fig. 22. – ?Not Hirohito 1995: 297, 

fig. 105d–g. – Migotto 1996: 40, fig. 8e–f. – Calder

222 

Fig. 67. Macrorhynchia philippina Kirchenpauer, 1872; A, 

Indonesia; B–E, Kei Island Expedition, Ambon harbour. A. 

Silhouette of colony fragment. B. Hydrocladial segment. C. 

Rim of hydrotheca in oblique view, note abcauline tooth, 

same scale as B. D. Oblique view of segment of primary 

tube, with apophysis (pointing towards left), nematothecae, 

and mamelon (on apophysis). E. Phylactocarp with 

gonotheca containing a male medusoid, tissue stippled. – 

Scales: A = 2 cm; B–C = 50 µm; D = 0.1 mm; E = 0.2 mm. 

P. SCHUCHERT 

1997: 66, fig. 21. – Watson 1997: 538, fig. 8F. – Watson 

2000: 67, fig. 53A–D. – Ansín Agís, Ramil & Vervoort 

2001: 46, fig. 46, bibliography, synonymy. 

Lytocarpus philippinus. – Pictet 1893: 60, pl. 3: fig. 53. – 

Nutting 1900: 122, pl. 31: figs 4–7. – Weltner 1900: 587. 

– Billard 1913: 78, fig. 63. – Vervoort 1941: 225. – Fraser 

1944: 419, pl. 93: fig. 410. – Vervoort 1968: 88, fig. 41. 

– Millard & Bouillon 1973: 93. – Millard 1975: 449, fig. 

138A–C. 

?Lytocarpus balei. – Leloup 1930b: 8, fig. 6, pl. 1: fig. 3. 

[Not Macrorhynchia balei (Nutting, 1905)] 

Lytocarpus crosslandi Ritchie, 1907: 511, pl. 24: fig. 11, pl. 

26: figs 2–4. 


Kei Islands Expedition stations: 11, with gonothecae. – 31. – 

107. – Kei Islands Expedition, Ambon, harbour pier, 4 Mar 

1922, with gonothecae. – Kei Islands Expedition, Lonthoir 

Channel, Banda Islands, 25 m, 11 Jun 1922. – Kei Islands 

Expedition, Bay of Ambon, Feb 1922. – MHNG INVE 

32228, as Lytocarpus philippinus, material of Pictet (1893), 

Ambon Harbour. 

Description 

Colonies 5–40 cm high, much branched, multipinnate, 

stem and branches polysiphonic, thinning 

in distal ramifications, only short terminal 

portions monosiphonic. Stem and branches composed 

of a superficial primary tube and a bundle 

of auxiliary tubes, primary tube of side-branches 

originating from auxiliary tubes of sister branch. 

Primary tube with hydrocladia, nodes may be 

present in distal regions, each segment with a 

hydrocladial apophysis, a broad median inferior 

nematotheca, a nematotheca on side of apophysis, 

and a mamelon on apophysis. 

Hydrocladia alternate, soft, shifted to anterior 

side of primary tube, regularly segmented by 

transverse to slightly oblique nodes, each segment 

with two internal ribs, these variably developed, 

up to 18 hydrothecae per hydrocladium. 

Hydrotheca sac-shaped, total height 0.32 mm, 

diameter in middle 0.11 mm, upper third curving 

away, opening oblique, margin with two rounded 

lateral cusps and a median abcauline tooth, the 

latter variably developed, between margin and 

median inferior nematotheca a thick shelf projecting 

halfway into hydrotheca, shelf in side 

view triangular. Hydranth with 8–10 tentacles. 

Nematothecae with very large mastigophores 

(80 µm long). Median inferior nematotheca conical 

in side view, free part tubular (not guttershaped), 

about 90 mm long, reaching beyond


margin of hydrotheca, with three openings: one 

terminal, one on upper surface where becoming 

free, one just below the latter leading into hydrothecal 

cavity (foramen). Lateral nematothecae 

tubular, inclined forward, overtopping somewhat 

hydrothecal margin, one or two openings: 

one terminal and one near base on upper surface, 

the latter not always visible. 

Gonothecae on modified hydrocladia (phylactocarps), 

one or two per phylactocarp. Phylactocarps 

composed of one hydrocladial segment 

with hydrotheca as in normal hydrocladia, followed 

by cylindrical segments with one or two 

nematothecae. Gonotheca attached to segment 

following hydrothecate segment, lens-shaped, 

diameter 0.6 mm; gonophore medusoid, with 

spadix, bell margin with granules. 

Remarks 

Hirohito’s (1983, 1995) material allocated to this 

species had rather thin intrathecal septae, had 

several gonothecae per phylactocarp, and was 

apparently larviparous. I therefore doubt that Hirohito’s 

samples belonged to M. philippina. The 

increased number of gonothecae and the lamellar 

intrathecal septae match better M. balei (Nutting, 

1905). Contrary to this, Leloup’s (1930b) specimen 

identified as M. balei appears indistinguishable 

from M. philippina. 

Distribution 


Type locality: Manila, Philippines. 

Macrorhynchia phoenicea (Busk, 1852) 

Figs 68–69. 

Plumularia aurita Busk, 1852: 397. 

Plumularia phoenicea Busk, 1852: 398. 

Aglaophenia rostrata Kirchenpauer, 1872: 45, pl. 1: fig. 25, 

pl. 6: fig. 25. – Weltner 1900: 588. 

Lytocarpus spectabilis Allman, 1883: 43, fig. 2, pl. 15: figs 

1–5. 

Aglaophenia phoenicea. – Bale 1884: 159, pl. 15: figs 1–5, 

pl. 17: figs 1–4, pl. 19: fig. 31. 

?Aglaophenia disjuncta Pictet, 1893: 59, pl. 3: figs 51–52. 

Lytocarpus phoeniceus. – Billard 1910: 48, fig. 22. – Billard 

1913: 74, figs 60–61. – Weltner 1900: 588. – Leloup 

1930b: 10, fig. 7, pl. 2: fig. 1. – Millard & Bouillon 1973: 

94. – Millard 1975: 451, fig. 137D. 

Macrorhynchia phoenicea. – Mammen 1967: 313, figs 108– 

109. – Rho 1967: 348, fig. 8. – Ryland & Gibbons 1991: 

555, fig. 23. – Hirohito 1995: 299, fig. 106a–e. 

223 

Macrorhynchia phoenicia.– Watson 2000: 68, fig. 54A–E. 


Kei Islands Expedition stations: 18. – 19, with gonothecae. – 

24. – 26, with gonothecae. – 57. – 67. – 69. – 71, with 

gonothecae. – 72. – 106. – 107. – Kei Islands Expedition, Kei 

Islands, Tual, 2 m, 28 Mar 1922, with gonothecae. – Kei 

Islands Expedition, Kei Islands, Tual, 22 Mar 1922, with 

gonothecae. – Kei Islands Expedition, Banda Islands, Neira 

Island, 25 m, 14 Jun 1922. 


Somewhat similar to Macrorhynchia philippina, 

but branching more regular, hydrocladia more 

bristly, denser, lengths quite homogenous, about 

12 hydrothecae per hydrocladium; abcauline horizontal 

shelf in hydrotheca thin and not triangular, 

height of hydrotheca smaller (0.22–0.25 

mm), free abcauline wall short, margin without 

abcauline tooth, lateral margin with two irregular 

cusps; majority of lateral nematotheca directed 

towards above; both nematothecae of hydrocaulus 

with two openings of different size. Gonotheca 

lens-shaped, less flattened but also with 

sharp edge along circumference. Nematothecae 

of phylactocarps in three rows. 

Description 

See Millard (1975), Ryland & Gibbons (1991), 

and Watson (2000). 

Remarks 

The bristly, neatly regular hydrocladia of equal 

length (Fig. 68) make large and fully grown 

Macrorhynchia phoenicea (Busk, 1852) to some 

degree recognizable even without the aid of a 

microscope. The hydrothecae and the internodes 

are quite variable (Fig. 68C–E). Especially the 

outline of the lateral rim of the hydrotheca is very 

variable. Bale (1884) discussed the variability of 

this species. 

The gonophores seen in the present material 

are likely sessile sporosacs, female ones containing 

10–16 eggs. 

The samples from stations 24, 26, and 57 

deviate somewhat from the others (Fig. 69). The 

colonies are smaller (6 cm), more gracile, they 

have longer internodes (0.30–0.34 mm), thinner 

hydrocladia, the lateral nematothecae of the 

proximal hydrothecae are directed in the direc-

224 

tion of the hydrothecal opening and not towards 

above, and the phylactocarps have only two rows 

of nematothecae instead of three as observed in 

the other samples. These samples came from 

P. SCHUCHERT 

Fig. 68. Macrorhynchia phoenicea (Busk, 1852); A, station 71; B & F, station 19; C–D, Tual; E, Neira Island. A. Colony 

silhouette. B. Frontal view of segment of primary tube, with apophysis (pointing towards left), nematothecae, and mamelon 

(on apophysis). C–E. Hydrocladial segments of different colonies, note variation of rim, length of median nematotheca, and 

length of segment. F. Phylactocarp with gonotheca containing eggs (stippled). – Scales: A = 2 cm; B = 0.1 mm; C–E = 50 µm; 

F = 0.2 mm. 

deeper waters (90–200 m), which could perhaps 

explain the differences, but they could as well 

also belong to a different species. This material 

resembles M. phoenicea described by Ryland &


Fig. 69. Macrorhynchia phoenicea (Busk, 1852); variant morphotype from station 24. A. Colony silhouette. B. Hydrocladial 

segment, note elongated shape (compare Fig. 68C–E). C. Variation of lateral nematotheca and hydrothecal margin within one 

hydrocladium, proximal hydrotheca below, distal one at top, note second opening in lateral nematotheca of middle region, 

same scale as B. – Scales: A = 1 cm; B–C = 50 µm. 

Gibbons (1989). The morphology approaches 

also the one of material described by Pictet 

(1893) as Aglaophenia disjuncta, but the internodes 

and hydrothecae are less elongated. Bedot 

(1926) considered Aglaophenia disjuncta Pictet, 

1893 as a synonym of M. phoenicea and a reexamination 

of the type material of A. disjuncta 

(MHNG INVE 25025, Bay of Ambon, Moluccas, 

80 m) indeed confirmed the close resemblance. 

Aglaophenia disjuncta, however, is characterized 

by very long hydrocladial internodes 

(Fig. 70), while the hydrothecae appear not distinguishable 

from M. phoenicea. The observed 

internode length (0.35–0.40 mm), however, is 

perhaps beyond the variation observed for M. 

phoenicea (0.27–0.34 mm, cf. also Figs 68C–E 

and 69B). Because the gonosome of Aglaophenia 

disjuncta remains also unknown, I prefer to 

regard it as only questionably conspecific with 

M. phoenicea. 

Distribution 

Australia, Indonesia, Malay Peninsula, New 

Guinea, Philippines, South China Sea, Japan, 

225 

Fig. 70. Aglaophenia disjuncta Pictet, 1893; type material. 

Hydrocladial segment. – Scale: 50 µm.

226 

Polynesia, tropical Indian Ocean, southern Africa. 

Type locality: Torres Strait, Australia. 

Macrorhynchia balei (Nutting, 1905) 

Fig. 71. 

Lytocarpus balei Nutting, 1905: 954, pl. 6: fig. 1, pl. 13: figs 

7–8. – in part Stechow 1909: 99, pl. 6: figs 12–13. – 

Billard 1913: 81, fig. 66. – Stechow 1919: 134. – Nutting 

1927: 236. – Vervoort 1941: 226, fig. 9. – Hirohito 1995: 

297, fig. 105a–c. [Not Lytocarpia balei (Nutting, 1927)] 

Not Lytocarpus balei. – Leloup 1930b: 8, fig. 6, pl. 1: fig. 3. 

[= M. philippina] 

?Macrorhynchia philippina. – Hirohito 1983: 78, fig. 41. – 

Hirohito 1995: 297, fig. 105d–g. [Not Macrorhynchia 

philippina Kirchenpauer, 1872] 


USNM 22220, Albatross Station 3852, South of Molokai, 

47–115 fathoms (86–210 m), fragmented colony, with numerous 

phylactocarps, not labelled as type material, but 

locality and collector clearly identifies it as such. 


Kei Islands Expedition station 57. – Kei Islands Expedition, 

Bay of Ambon, 90 m, 2 Mar 1922, with 4 gonothecae on 

young phylactocarps. – Kei Islands Expedition, Bay of 

Ambon, 45–90 m, 2 Mar 1922. – Kei Islands Expedition, 

Bay of Ambon, 13–18 m, 28 Feb 1922. – USNM 68534, loc. 

Philippines, material described in Nutting (1927). 


Similar to Macrorhynchia philippina, but differs 

in forming smaller sized colonies, thicker hydrocladia 

with up to 17 hydrothecae; hydrotheca 

with lamellar adcauline septum, hydrothecal rim 

with or without abcauline tooth; lateral nematothecae 

either parallel to upper wall of hydrotheca 

or pointing towards above (varies from proximal 

to distal of hydrocladium, Fig. 71D), rim of opening 

of median inferior nematotheca often curved; 

lateral rim of hydrothecae with two rather variably 

shaped cusps, lateral rim can also be almost 

smooth. On rear wall of hydrocladia, auxiliary 

tubes, and primary tubes numerous small pores 

(nematopores) plugged with clusters of nematocysts 

(isorhizas) (Fig. 71B). Phylactocarps 2/3 as 

long as hydrocladia, with up to 8 lenticular gonothecae, 

these alternately shifted to the right and 

left. 

Differs from M. phoenicea by its more irregular 

colonies, longer hydrocladia, forward directed 

lateral nematothecae, rear nematopores, 

and the number of gonothecae per phylactocarp. 

P. SCHUCHERT 

Measurements: colony height 4–10 cm, total 

height of hydrotheca 0.25–0.32 mm, larger isorhiza 

about 85 µm long (in median inferior 

nematotheca), smaller isorhiza about 40 µm long 

(in rear nematopores). Female gonothecae contain 

4–6 eggs. Gonotheca diameter 0.6 mm. 

Remarks 

The numerous nematopores on the rear side of 

the hydrocladia, primary tubes, and auxiliary 

tubes make Macrorhynchia balei recognizable 

even in the absence of phylactocarps. These nematophores 

are funnel-shaped holes in the periderm 

that are plugged by a bundle of elongated 

nematocysts (see Fig. 71B). If the capsules are 

lost in preserved material, the nematopores are 

not conspicuous. However, if these isorhizas are 

discharged so that the bundle of shafts protrude 

trough the pore, the pores are easy to see and very 

characteristic. The number of pores per hydrocladial 

segments varies from zero to two, mostly 

they are at the level of the internal ribs. The pores 

are usually absent in the distal segments of the 

hydrocladium. The auxiliary tubes also have 

these pores, usually in several rows (Fig. 71D). 

As in the hydrocladia, also here the density of the 

pores is variable between colonies. 

No such nematopores were reported in any of 

the available descriptions of this species (see 

synonymy). The type material of Macrorhynchia 

balei was therefore re-examined for this study. 

Although the soft tissue of the type material is is 

not well preserved, perhaps due to mechanical 

damage during the collecting procedure, some 

hydrocladia with intact soft tissue clearly possess 

identical nematopores and tufts of isorhiza capsules 

just like in the Indonesian material. The 

dimensions and morphology of hydrotheca and 

nematothecae were also indistinguishable from 

the Indonesian material, which is thus almost 

certainly conspecific with Nutting’s original material. 

Nutting (1927) also attributed material 

from the Philippines to the present species. Also 

this material could be re-examined. It is more 

robust than the type colony, infertile, and the soft 

tissue is almost completely lost. There are, however, 

distinct pores on the rear side of the hydrocladia, 

which renders this identification quite 

secure.


Fig. 71. Macrorhynchia balei (Nutting, 1905); A–B & D, Bay of Ambon; C, station 57; F after type material. A. Colony 

silhouette. B. Hydrocladial segment, note clusters of nematocysts at rear side. C. Variation of median inferior nematotheca and 

abcauline tooth, same scale as B. D. Variation of lateral nematotheca from proximal (bottom) to distal (top) part of 

hydrocladium, same scale as B. E. Side view of auxiliary tube wall with nematopores and nematocyst clusters, same scale as 

B. F. Phylactocarp with gonothecae, note that the hydrotheca at the base of the phylactocarp is not visible in this figure. – 

Scales: A = 1 cm; B–E = 50 µm; F = 0.5 mm. 

The curved margin of the distal opening of the 

median nematotheca is also quite characteristic 

(Fig. 71B), although not all nematothecae have it 

(Fig. 71C). 

Macrorhynchia balei was originally described 

by Nutting based on material from Hawaii. Subsequently, 

Stechow (1909) reported it from Japan. 

Later, however, Stechow (1919: 134) referred 

part of this material to Macrorhynchia 

singularis (Billard, 1913). Billard (1913) identified 

infertile material from Indonesia as M. balei. 

227 

Stechow (1919: 129) thought that Billard’s material 

did not belong to M. balei and he referred it to 

Lytocarpia(?) graeffei (Kirchenpauer, 1876), a 

problematic species. Kirchenpauer (1876) provided 

only the name Aglaophenia graeffii, this 

without any diagnosis or illustration. This nominal 

species must therefore be seen as invalid, a 

nomen nudum. It appears, however, that Stechow 

(1919) based his description and figure on 

Kirchenpauer’s original material, so Stechow 

thus becomes the author of this species. Stechow

228 

based his description of Lytocarpia graffei on a 

small, juvenile colony. The colony was monosiphonic 

and had no gonothecae. It must be considered 

as unrecognizable. Stechow (1919) distinguished 

it from M. balei on account of the 

shape of the bottom of the hydrotheca: rounded 

in M. balei, with a step in Lytocarpia graffei. This 

character is of little use, as usually all intermediates 

can be found in Macrorhynchia colonies. 

Leloup (1930b) also contested Stechow’s view, 

however, Leloup’s (1930b: fig. 6) material of M. 

balei appears indistinguishable from M. philippina 

because his figures show a thick, triangular 

intrathecal septum. Hirohito (1983, 1995) again 

described Japanese material of M. balei. Hirohito 

distinguished his material from M. philippina 

solely on account of the length and thickness of 

the intrathecal septum. However, the figures of 

M. philippina given by Hirohito (1983, 1995), 

are more typical for M. balei: the upright lateral 

nematotheca and the numerous gonothecae on 

the phylactocarps. Because Hirohito (1983) also 

described female gonothecae containing planulae, 

thus being larviparous and not releasing 

medusoids as seen in typical M. philippina, it 

seems more likely that this material was also M. 

balei. Hirohoto’s material should be re-examined 

for the presence of nematopores. 

Distribution 

Hawaii, Indonesia, Philippines, Japan. Type locality: 

Off south coast of Molokai, Hawaiian 

archipelago, 86–210 m. 

Macrorhynchia singularis (Billard, 1908) 

Fig. 72. 

Plumulariidae spec. IV von Campenhausen 1896b: 317, pl. 

15 fig. 5. 

Lytocarpus philippinus var. singularis Billard, 1908b: 112, 

figs A–B. 

Lytocarpus singularis Billard, 1913: 79, figs 64–65. 

Lytocarpus balei. – In part Stechow 1909: 99, pl. 6: fig. 12. 

– Stechow 1919: 134. 


Kei Islands Expedition stations: 18. – 40. – Kei Islands 

Expedition, Bay of Ambon, 45–90 m, 2 Mar 1922. – Kei 

Islands Expedition, Bay of Ambon, 90 m, 2 Mar 1922. 


Similar to Macrorhynchia philippina, but colo- 

P. SCHUCHERT 

Fig. 72. Macrorhynchia singularis (Billard, 1908); station 

40. A. First internode of hydrocladium, note enlarged lateral 

nematotheca (dotted: nematocyst). B. Second segment of 

hydrocladium with characteristic thick median inferior nematotheca. 

– Scale: A–B 50 µm. 

nies smaller (up to 10 cm), one lateral nematotheca 

of first hydrocladial segment much enlarged 

and directed towards rear, opposite nematotheca 

of same segment small, free part of 

median nematotheca very short; median nematotheca 

of segments distal to first one mostly 

much enlarged and thick, lateral nematothecae 

usually small. Some lateral nematothecae of 

more distal segments can also be enlarged on one 

side, as well as some median inferior nemat-


othecae can be short. Hydrothecal margin with 

two broad lateral lobes or irregular, abcauline 

side with pointed tooth. 

Remarks 

Billard (1908b) first regarded M. singularis as 

a variety of M. philippina, but in his 1913 publication 

he raised its status to the species level. 

Macrorhynchia singularis indeed resembles M. 

philippina, but the unilaterally hypertrophied lateral 

nematothecae as well as the alternately extremely 

short or very thick median inferior nematothecae 

make this morphotype rather distinct 

and easy to recognize (Fig. 72A–B). Stechow 

(1919) found Japanese material from Sagami 

Bay that only partially matched Billard’s description. 

It had one enlarged lateral nematotheca on 

the first segment, but the median inferior ones 

were normal. Stechow (1919) made some comments 

that let one suspect that he doubted somewhat 

the validity of M. singularis. In his survey of 

the thecate hydroids of Sagami Bay, Hirohito 

(1995) did not include M. singularis. 

Distribution 

Indonesia, ?Japan. Type locality: Salawati Island, 

NW New Guinea, 1.701°S, 130.785°E, 32 

m. 

Monoserius pennarius (Linnaeus, 1758) 

Fig. 73. 

Sertularia pennaria Linnaeus, 1758: 813. 

Aglaophenia spicata Lamouroux, 1816: 166. – Billard 1909: 

329. 

Plumularia Banksii Gray, 1843: 294. – Billard 1910: 48. 

Aglaophenia secunda Kirchenpauer 1872: 35, pl. 1: fig. 15, 

pl. 2: fig. 15, pl. 3: fig. 15. – Marktanner-Turneretscher 

1890: 273. – Billard 1909: 329. 

Aglaophenia crispata Kirchenpauer, 1872: 36, pl. 1: fig. 16, 

pl. 2: fig. 16, pl. 3: fig. 17. – Billard 1909: 329. 

Not Aglaophenia spicata. – Kirchenpauer 1872; 27, pl. 1: 

fig. 12, pl. 2: fig. 11, pl. 4: fig. 11, [= A. cupressina 

Lamouroux, 1816]. 

Lytocarpus secundus. – Allman, 1883: 42, pl. 14. – Jäderholm 

1903: 298. – Billard 1908c: 940. 

Lytocarpus fasciculatus Thornely, 1904: 123, pl. 3: figs 3, 

3A, 3B. 

Lytocarpus pennarius. – Billard 1909: 329. – Ritchie 1910a: 

19, pl. 4: fig. 2. 

Hemicarpus fasciculatus. – Billard 1913: 83, figs 68–69, pl. 

5: figs 41–42. 

Hemicarpus banksi. – Bale 1924: 263, fig. 17a. 

229 

Monoserius fasciculatus. – Leloup 1932: 165, fig. 28. – 


Monoserius banksii. – Ralph 1961b: 56, fig. 8h 

Monoserius pennarius. – Mammen 1967: 307, figs 108–109. 

Monoserius fasciculatus. – Mammen 1967: 310. 


Kei Islands Expedition stations: 65, incipient gonocladium 

present. – 67, with male gonothecae. – 69. – 70. – 83. – 102. 

– 103. – 105. – 110. – 114. – Kei Islands Expedition, 

Samalon Island, Ujungpandang, Sulawesi, 35 m, 28 Jun 

1922. – Kei Islands Expedition, Taka Bako, Ujungpandang, 

Sulawesi, 25 m, 27 Jun 1922. 

Description 

Colonies forming single stems, rooted in sediment 

by a tangled mass of fibre-like stolons, stem 

height reaching 100 cm and more, flexible, limp 

when out of water. Stem polysiphonic, with regularly 

spaced pinnate side-branches. Basal part of 

stem in younger colonies pinnate through alternate 

hydrocladia, hydrocladia arise from superficial 

primary tube; in more distal part where there 

are pinnate side-branches and in larger colonies 

without pinnate base there is no primary tube, 

stem thus formed by auxiliary tubes only. Sidebranches 

originate from auxiliary tubes of main 

stem, feather-like through dense hydrocladia, 

side-branches alternate, in two rows, the two 

rows forming an angle of 90° or less, sidebranches 

thus directed towards one side (depending 

on view). Axis of side-branches polysiphonic 

but thinning to monosiphonic, with superficial 

primary tube bearing alternate hydrocladia. Primary 

tube with short apophyses for hydrocladia, 

each apophysis associated with three nematothecae: 

one on apophysis, one on side, one below. 

Hydrocladia straight, stiff, dense, inclined towards 

hydrocaulus at an angle of about 40°, with 

or without transverse nodes delimiting segments, 

spacing of hydrothecae variable: hydrothecae either 

slightly overlapping (Fig. 73C) or well separated 

(Fig. 73D). Internal ribs not much developed, 

usually two originating from rear wall of 


Hydrotheca campanulate, nearly parallel to 

hydrocladial axis, 0.27–0.35 mm high, diameter 

at rim 0.15–0.17 mm, adcauline side completely 

adnate, opening-plane perpendicular to hydrocladial 

axis, rim with a large abcauline tooth and 

4–5 triangular cusps on both lateral sides. Marginal 

abcauline tooth rectangular in frontal view,

230 

P. SCHUCHERT 

Fig. 73. Monoserius pennarius (Linnaeus, 1758); A, station 70; B–C, E–F, station 67; D, station 102. A. Silhouette of young 

colony. B. Hydrotheca in oblique view, note abcauline gutter-shaped tooth. C. Two hydrothecae in side view, from colony with 

narrow spacing, same scale as B. D. Two hydrothecae from colony with widely spaced hydrothecae, same scale as B. E. 

Gonocladium with three gonothecae, note that there is only one row of nematocladia. F. Part of gonocladium with 

nematocladium. Scales: A = 2 cm; B–D = 0.1 mm; E = 0.5 mm; F = 0.1 mm.


curved in side view, with longitudinal gutter-like 

depression along its entire length, gutter also 

somewhat continued on abcauline wall of hydrotheca. 

Lateral cusps of variable height, the two in 

the middle more prominent. 

Nematothecae all with finely crenulated rims. 

Median inferior nematotheca reaching to middle 

or up to 2/3 of hydrotheca, free part of variable 

length, top side open and thus gutter-like, opening 

into hydrotheca (foramen) present, often difficult 

to see, perhaps also obliterated. Lateral 

nematothecae cup-shaped, small, 0.1–0.12 mm 

long, opening facing towards above. 

Gonothecae borne on modified hydrocladia, 

(gonocladia), about every third to fifth hydrocladium 

may be modified into a gonocladium. 

Gonocladia straight, fully mature ones reach the 

same length as other hydrocladia. First segment 

as in normal hydrocladia, thus with a hydrotheca, 

along rest of gonocladium no hydrothecae, but 

with one row of spine-like processes (nematocladia) 

bearing two rows of nematothecae along 

their sides. Gonocladial axis also with nematothecae. 

Nematothecae adnate on one side. Gonothecae 

arise at base of nematocladia, lens-shaped 

but not much flattened, diameter 0.7 mm. 

Remarks 

The genus Monoserius Marktanner-Turneretscher, 

1890 is here used for this species and 

Hemicarpus Billard, 1913 is regarded as a synonym 

of it. With its gonocladia having a single row 

of side-branches (nematocladia), this is quite a 

distinct genus. 

Mammen (1967) is here followed in regarding 

M. pennarius (L.) and M. fasciculatus (Thornely, 

1904) as conspecific. Billard (1909, 1910) examined 

the type material of Sertularia pennaria 

Linnaeus, 1758; Aglaophenia spicata Lamouroux, 

1816; and Plumularia Banksii Gray, 1843 

and he concluded that they are conspecific. He 

also included Aglaophenia secunda Kirchenpauer 

1872 and Aglaophenia crispata Kirchenpauer, 

1872 in this synonymy. It is therefore 

somewhat surprising that Billard (1913) regarded 

M. fasciculatus (Thornely, 1904) as valid 

and did not discuss the differences to M. pennarius. 

In the present material two variants are dis- 

231 

cernible: a variant with more robust, thick stems 

and long branches and a gracile variant with thin 

stems and short side-branches. These differences 

are here seen as age related. 

Distribution 

India, Ceylon, Indonesia, Philippines, Taiwan, 

Southern Japan, Palau, New Zealand. Type locality: 

Unknown. 

Cladocarpus keiensis new species 

Fig. 74. 

Type material: 

Holotype: ZMUC, Kei Islands Expedition station 24, Kei 

Islands, 15 Apr 1922, hard bottom, colony fragmented; part 

of this colony as schizotype slides in MHNG, collection no. 

INVE 32487. Type locality: Kei Islands Expedition station 

24, 5.62°S, 132.93°E, 100 m. 

Description 

Colony 6 cm high, stem with a few sidebranches, 

stem polysiphonic, composed of one 

superficial primary tube bearing hydrocladia 

(lost in lower part) and bundle of about 8 auxiliary 

tubes, number of auxiliary tubes reduced 

towards distal, terminal part of stem monosiphonic; 

few side-branches present, structured 

like stem, lower ones slightly polysiphonic, 

distal ones monosiphonic, primary tube of sidebranches 

originates from primary tube of stem. 

Auxiliary tubes with a row of nematothecae in 

groove separating two adnate tubes, nematothecae 

of auxiliary tube similar to those of primary 

tube. Primary tube segmented in more distal 

parts, internodes long (0.9 mm); in distal third of 

internode an apophysis for the hydrocladium, 

with three nematothecae: one axillary and two 

median in lower half of segment. Nematothecae 

oval, free end gutter-like. 

Hydrocladia on stem and side-branches in two 

rows, alternate, stiff, thin, up to 2 cm long, the 

two rows not in one plane but at variable angle, 

angle may be smaller than 90°. Hydrocladium 

homomerously segmented by slightly oblique 

nodes, segments 0.65–0.75 mm long, diameter 

at nodes 0.15–0.2 mm, each segment with one 

hydrotheca and three nematothecae: two laterals 

and one median inferior; internodes with regular

232 

internal thickenings (ribs): 7–8 semicircular ones 

along adcauline wall of hydrotheca, one circular 

at base of median inferior nematotheca. 

Hydrotheca elongate, conical, depth 0.5 mm, 

opening diameter 0.2 mm, adcauline wall completely 

adnate, abcauline wall mostly straight or 

very slightly S-shaped, opening-plane perpendicular 

to internode axis, margin smooth except 

for a sharp rectangular abcauline cusp, cusp not 

P. SCHUCHERT 

Fig. 74. Cladocarpus keiensis new species. A. Part of stem in polysiphonic region, with base of hydrocladium; note presence 

of nematothecae on auxiliary tube (left). B. Hydrocladial segment in lateral, transparent view. C. Hydrocladial segment in 

oblique view, note intrathecal septum and ridge (stippled). D. Median inferior nematotheca. E. Lateral nematotheca seen from 

inner side, note that two lobes formed by drop-shaped emargination can also be fused, same scale as D. F. Hydrocladium with 

gonocladium bearing three juvenile gonothecae, note presence of hydrothecae on gonocladium as well as single row of 

nematothecae. – Scales: A = 0.2 mm; B–C = 0.1 mm; D–E = 50 µm; F = 0.5 mm. 

gutter-like. Hydropore near base of adcauline 

side. At lower fourth of hydrotheca an internal 

adcauline septum spanning half the hydrothecal 

diameter, scoop-shaped, directed obliquely upward, 

lateral sides attached to hydrotheca and 

continued as a looped ridge to abcauline wall 

where both ends meet (Fig. 74B–C). Septum and 

ridge very conspicuous, present in all hydrothecae.


Lateral nematothecae tubular, distal half extending 

beyond hydrotheca, bent at level of 

hydrothecal margin, upper part upright, lower, 

adnate part oblique, one circular terminal opening, 

inner wall with either a deep, drop-shaped 

emargination or a similarly shaped hole (Fig. 

74E). Median inferior nematotheca below hydrotheca 

and just reaching somewhat beyond its 

bottom, tubular, straight, lower half adnate, free 

part gutter-like. 

Gonothecae borne on modified hydrocladia 

(gonocladia) branching off from ordinary hydrocladia, 

branching point near base of a hydrotheca. 

Gonocladia unpaired, straight, closely resembling 

ordinary hydrocladia, with a few segments 

bearing a hydrotheca and nematothecae, 

these segments thus identical to the ones of ordinary 

hydrocladia, intercalated between them 2–3 

internodes bearing a gonotheca, each internode 

with 2–3 nematothecae, nematothecae these internodes 

in one median row, thus not paired, 

resembling median inferior nematothecae. Gonocladium 

with regular internal ribs. 

Observed gonothecae all at beginning of development 

only, funnel-shaped, circular crosssection. 

Etymology 

The name keiensis refers to the type locality in the 

channel between the two main islands of the Kei 

Archipelago. 

Remarks 

Cladocarpus keiensis resembles Cladocarpus 

sibogae, the type locality of which is only 8–9 

nautical miles distant. They differ, however, in 

a number of independent details. Cladocarpus 

sibogae has median inferior and lateral nematothecae 

with slit-like openings which are not 

gutter-shaped or tubular (see Ramil & Vervoort 

1992: fig. 27f), the hydrothecal margin is undulated, 

it lacks the large intrathecal septum and 

the looped ridge, the gonocladium has no interspersed 

segments with hydrothecae, and the nematothecae 

of the gonocladium are in two rows. 

Further differences are found in the unbranched 

stem and the generally larger dimensions of internode 

length and hydrotheca size. Cladocarpus 

multiseptata Bale, 1915, is also similar but this 

233 

species has gonocladia with nematothecae in two 

rows and without hydrothecae. There are more 

such similar species and their differences are 

discussed in Vervoort (1966), Rees & Vervoort 

(1987), Ramil & Vervoort (1992), and Ansín 

Agís et al. (2001). Cladocarpus keiensis differs 

from all of them by its peculiar gonocladium and 

the intrathecal septum continued as a looped 

ridge. 

The gonocladium (phylactocarp) of Cladocarpus 

keiensis with its interspersed hydrothecate 

elements immediately suggests its origin 

from an ordinary hydrocladium and could represent 

the least derived phylactocarp morphology 

found in this genus. The gonothecae of the type 

specimen were all juvenile, but clearly recognizable 

as incipient gonothecae (Fig. 74F). 

Distribution 

Only known from the type locality: Kei Islands 

Expedition station 24, 5.62°S, 132.93°E, 100 m. 

Lytocarpia angulosa (Lamarck, 1816) 

Fig. 75. 

Plumularia angulosa Lamarck, 1816: 126. 

Aglaophenia angulosa Lamouroux, 1816: 166. 

Plumularia Huxleyi Busk, 1852: 395. 

Acanthocladium Huxleyi. – Allman 1883: 33, pls 9 & 20: 

figs 1–3. 

Aglaophenia Huxleyi. – Bale 1884: 161, pl. 15: fig. 6, pl. 17: 

fig. 8. 

Thecocarpus angulosus. – Billard 1907: 326, fig. 2, revision. 

– Billard 1913: 85, figs 70–74. 

Acanthocladium studeri Weltner, 1900: 588, pl. 46: figs 4– 

7. 

Acanthocladium angulosum. – Stechow & Müller 1923: 

478. 

Lytocarpia angulosa. – Watson 2000: 64, fig. 51A–G. 


Kei Islands Expedition stations: 15, with gonothecae. – 16. – 

18. – 21. – 24. – 26. – 30, with gonothecae. – 37. – 53. 

Description 

Colonies forming single stems, rooted in sediment 

by tangled mass of fibre-like stolons, stem 

height reaching 60 cm and more, flexible, limp 

when out of water, polysiphonic, furnished all 

around with helically arranged pinnate sidebranches. 

Stem only occasionally with hydrocladia 

arising from a primary tube, hydrocladia

234 

often lost, some replaced by pseudophylactocarps. 

Auxiliary tubes can also bear pseudophylactocarps; 

they can also be present on sidebranches, 

sometimes they are rare or absent. 

Pseudophylactocarps are modified hydrocladia 

without hydrothecae, highly flexible, com- 

P. SCHUCHERT 

Fig. 75. Lytocarpia angulosa (Lamarck, 1816); A, Indonesia, Kei Islands collection; B–D, station 18; E, station 15. A. Distal 

fourth of a colony. B. Hydrocladial segment, note abcauline marginal tooth. C. Same hydrocladial segment seen from left and 

right, note differently shaped lateral nematothecae. D. Modified hydrocladium (pseudophylactocarp) from stem, same scale as 

C. E. One costa of a corbula seen from inner side. – Scales: A = 2 cm; B = 50 µm; C–D = 0.1 mm; E = 0.2 mm. 

posed of short segments, each segment with 

three nematothecae, these resembling to a pair of 

laterals and one median inferior nematotheca of 

normal hydrocladia. 

Axis of side-branches polysiphonic, monosiphonic 

at very ends only, with superficial pri-


mary tube bearing alternate hydrocladia, base of 

side-branches without oblique pinching (hingejoint). 

Hydrocladia straight, stiff, dense, inclined towards 

hydrocaulus at an angle of about 60°, up to 

5 mm long, with oblique nodes delimiting segments. 

The distal-most hydrocladia of a sidebranch 

can be transformed into spine-like processes 

bearing nematothecae. 

Hydrotheca semi-circular in side view, 0.21– 

0.25 mm high, adcauline side 2/3 adnate, opening-plane 

parallel to hydrocladial axis, almost no 

free abcauline side, rim with a large abcauline 

tooth, lateral margin undulated, with a horizontal, 

thin abcauline septum projecting into lumen 

of hydrotheca, free end of septum in-rolled. 

Median inferior nematotheca adnate along 

entire length of abcauline hydrothecal wall, total 

length less than height of hydrotheca, free part 

of variable length, top side of free part open 

and thus gutter-like, opening into hydrotheca 

(foramen) present. Lateral nematothecae cupshaped, 

broad, opening facing upward; the two 

lateral nematothecae of on hydrothecae are often 

unequally developed, especially in more proximal 

hydrothecae (Fig. 75C). 

Gonothecae borne on hydrocladium modified 

into corbula. Corbula as long as hydrocladia, axis 

without hydrothecae, with two rows of alternate 

costae. Costae solitary and not fused, up to 1.3 

mm long, each with a hydrotheca in lower part, 

distal part tapering, segmented, on lateral side of 

each segment two opposite, adnate nematothecae. 

Gonothecae attached below hydrotheca, lenticular 

to sac-shaped, 0.6 mm diameter; gonophore 

medusoid, bell margin with granules. 

Remarks 

The hydrotheca of Lytocarpia angulosa (Lamarck, 

1816) resembles somewhat the one of 

Macrorhynchia phoenicea, but its abcauline 

tooth, the gutter-shaped median inferior nematotheca, 

and the frequently unequal development 

of the lateral nematothecae of L. angulosa are 

sufficient to distinguish them. The colony form 

of the two species is quite different and so they 

are easily separable macroscopically (cf. Figs 

68A and 75A). 

Some of the examined gonothecae contain 

235 

gonophores that are clearly similar to the ones 

found in M. philippina, thus presumably liberable 

medusoids. The medusoids even have a 

ring of refringent granules along the bell margin. 

These medusoids are now known for quite a 

number of thecate hydroids (see Boero & Bouillon 

1989, Gravier-Bonnet & Migotto 2000). 

Likewise, the pseudophylactocarps are found in 

various species of tropical aglaophenids belonging 

to different genera (see also L. perarmata 

below). 

Distribution 

Northern Australia, Indonesia. Type locality: 

Australia. 

Lytocarpia delicatula (Busk, 1852) 

Fig. 76. 

Plumularia delicatula Busk, 1852: 396. 

Aglaophenia delicatula Bale, 1884: 167, pl. 14: fig. 4, pl. 17: 

fig. 11. – Borradaile 1905: 843, pl. 69: fig. 7. – Billard 

1913: 106, fig. 95. – Jäderholm 1920: 8, pl. 2: fig. 7. – 

Jarvis 1922: 350. – Pennycuik 1959: 185. – Watson 

2000: 57, fig. 46A–E. 

Thecocarpus delicatulus. – Millard & Bouillon 1973: 94, 

fig. 11J–K. – Millard 1975: 455, 139D–E. 


Kei Islands Expedition stations: 37, on sponge and stone. – 

67, part of plume. – 85, with gonothecae. – Kei Islands 

Expedition, Banda Islands, Neira Island, 20 m, 1 Jun 1922, 

on sponge. 

Description 

Colony pinnate, 3–12 cm, stem not branched, 

monosiphonic, bearing alternate hydrocladia, 

with prosegments, with one or two hingejoints, 

part above hinge-joint segmented through 

slightly oblique nodes, each segment bearing a 

hydrocladial apophysis with a mamelon and 

three nematothecae: one inferior anterior and one 

on each side of the apophysis. 

Hydrocladia up to 8 mm long, held obliquely 

to caulus, bearing anterior hydrothecae, homomerously 

segmented by transverse nodes, segments 

with weakly developed internal ribs. 

Hydrotheca campanulate, depth 0.21–0.23 

mm, covering nearly complete segment, adcauline 

side adnate; opening forming an angle of 

about 55° with segment, inclined towards below, 

margin with five cusps: one distinct abcauline

236 

tooth and on each lateral side two broader triangular 

cusps. On inside of lower part of hydrotheca 

a short adcauline shelf, shelf continued as 

ridge along hydrothecal wall towards front. 

Median inferior nematotheca adnate to abcauline 

hydrothecal wall to just below origin of 

abcauline tooth, free end rather short, guttershaped, 

reaching approximately to level of the 

tips of the marginal cusps; foramen into hydrotheca 

present but inconspicuous and small, may 

be obliterated. Lateral nematothecae curved, 

opening directed towards above, reaching beyond 

margin of hydrotheca. 

P. SCHUCHERT 

Fig. 76. Lytocarpia delicatula (Busk, 1852); A, Indonesia, Kei Islands collection; B–F, station 85. A. Colony silhouette. B. 

Two stem segments. C. Hydrotheca in oblique view. D. Hydrocladial segment from side. E. Hydrothecal tooth and median 

inferior nematotheca from hydrotheca on same hydrocladium as that shown in D, note the variability. F. Corbula containing 

gonothecae. – Scales: A = 1 cm; B, F = 0.2 mm; C = 0.1 mm; D, E = 50 µm. 

Corbula open, replacing a hydrocladium, first 

segment like in a normal hydrocladium with hydrotheca, 

followed by 6–7 segments bearing alternate 

ribs (costae). Costae thin, not flattened, 

not fused, near base a hydrotheca with associated 

lateral nematothecae; part of costa distal to hydrotheca 

with two rows of alternate nematothecae. 

Gonotheca attached on costal apophysis of 

corbula axis (rachis), oblong, flattened, 0.8–1.0 

mm long 

Remarks 

The corbulae of Lytocarpia delicatula (Busk,


1852) are relatively small. In the present material 

(Fig. 76F), the simultaneous presence of gonothecae 

with soft tissue and others that are already 

empty nevertheless suggests that the corbulae are 

mature. See also below for the distinction from 

the similar Lytocarpia phyteuma. 

Distribution 

Northern Australia, Great Barrier Reef, Indonesia, 

Seychelles, Maldives, Mozambique. Type 

locality: Torres Strait, Australia, 16 m. 

Lytocarpia phyteuma (Kirchenpauer, 1876) 

Fig. 77. 

Agalophenia phyteuma Kirchenpauer, 1876: 23. 

237 

Agalophenia elongata var. sibogae Billard, 1913: 103, figs 

92–93. 

Thecocarpus phyteuma. – Stechow 1919: 139, figs C2–D2. – 

Pennycuik 1959: 187. – Millard & Bouillon 1973: 95, 

fig. 11E–F. – ?Vervoort & Vasseur, 1977: 86, fig. 36. 

Lytocarpia phyteuma. – Ryland & Gibbons 1991: 548, figs 

18–19. – Watson 2000: 65, fig. 52A–G. 

Aglaophenia clavicula Whitelegge, 1899: 373, pl. 23: figs 

4–6. 

Thecocarpus leopoldi Leloup, 1930a: 1, fig. 1. – Leloup 

1930b: 11, figs 8–9, pl. 2: figs 2–3. – Vervoort & 

Vasseur, 1977: 86, revision. 


Kei Islands Expedition station 69. – Kei Islands Expedition, 

Banda Islands, Neira Island, 20 m, 1 Jun 1922, incipient 

corbulae with hydrothecae present. – Kei Islands Expedition, 

Banda Island, village of Waling, 20 m, 11 Jun 1922. 

– MHNG INVE 32597, Thailand, Andaman Sea, Koh Pee 

Pee, 10–15 m, 15 Apr 2000, coll. A. Faucci, with corbulae 

Fig. 77. Lytocarpia phyteuma (Kirchenpauer, 1876); A–C, Banda Islands; D–E, Andaman Sea. A. colony silhouette. B. Two 

stem segments. C. Hydrocladial segment from side. D. Corbula. E. Two costae of corbula. – Scales: A = 1 cm; B = 0.2 mm; C 

= 50 µm; D = 0.5 mm.

238 


Similar to L. delicatula, differing in: stems only 

up to 4 cm, hydrocladia wider spaced, stem without 

hinge-joints, prosegments not visible but 

with solitary nematothecae on proximal stemregion; 

hydrotheca deeper (0.26 mm), opening 

less inclined, lateral margin with three cusps, 

median inferior nematotheca reaches only to 

middle of hydrotheca; mature corbula long (2/3 

of hydrocladia), with fused broad ribs bearing 

only one row of nematothecae. 

Description of gonotheca 

Corbulae closed, length variable but may reach 

almost the length of a hydrocladium. First segment 

hydrothecate and identical to normal hydrocladium, 

then axis with two alternate rows of 

costae. Costae leaf-like, at base a hydrotheca on a 

lobe, distal rim of costa with a row of nematotheca, 

costae fused to form a tube, distal end 

mostly open, this even in corbulae with mature 

gonothecae. Lobe bearing hydrotheca can be 

elongated like a spur and may bear a terminal 

nematotheca. 

Description of trophosome 

See Stechow (1919) or Ryland & Gibbons 

(1991). 

Remarks 

The Indonesian material assigned here to Lytocarpia 

phyteuma (Kirchenpauer, 1876) had only 

one immature corbula. The hydrotheca on the 

corbula made it clear that it belonged to Lytocarpia. 

The trophosome matched quite well fertile 

material from the Andaman Sea as well as 

the description of Millard & Bouillon (1973), 

or Ryland & Gibbons (1991). It matched also 

Stechow’s (1919) re-description of the type specimen, 

although the median nematothecae of the 

type material are tubular and not gutter-shaped as 

observed here. All other authors describing material 

of L. phyteuma reported gutter-like median 

nematothecae. Millard & Bouillon (1973) interpreted 

this as an interspecific variation because 

such a variation is also known in from other 

aglaophenids. The material of Vervoort & Vasseur 

(1977) differs in that the lateral nemato- 

P. SCHUCHERT 

thecae extend much towards the rear side of the 

internode. Watson (2000) had therefore some 

doubts on the identity of this material. The Australian 

material of Watson (2000), however, also 

differs slightly from the Indonesian one in that 

the median nematotheca reaches much higher up, 

thus approaching the condition of L. delicatula. 

The size of the hydrotheca is apparently also 

smaller. 

The material of the present investigation is 

obviously identical to Billard’s (1913) Aglaophenia 

elongata var. sibogae from various Indonesian 

localities. Billard had apparently only infertile 

material at hand and his variant is therefore 

here regarded as a synonym of L. phyteuma. 

Aglaophenia elongata Meneghini, 1845 is a 

Mediterranean species (Svoboda & Cornelius 

1991). 

Lytocarpia leopoldi (Leloup, 1930) from New 

Guinea is very similar to L. phyteuma. The main 

distinguishing characters are the gutter-shaped 

median nematotheca, two nematothecae per 

cauline segment, and some aspects of the corbula. 

Vervoort & Vasseur (1977) found that the 

differences of the corbula are not significant and 

they synonymized the two names. As mentioned 

above, tubular or gutter-shaped median nematotheca 

is likely only representing intra-specific 

variation. The cauline nematothecae are sometimes 

not easy to observe, especially in slide 

preparations, and Leloup might have overlooked 

one. Lytocarpia leopoldi is therfore very likely a 

synonym of L. phyteuma, although for a final 

decision the type material of L. leopoldi should 

be re-examined. 

Distribution 

Polynesia, Great Barrier Reef, northern Australia, 

Indonesia, Seychelles. Type locality: 

Tonga Islands. 

Lytocarpia perarmata (Billard, 1908), n. comb. 

Fig. 78. 

Thecocarpus myriophyllum perarmatus Billard, 1908a: 74, 

fig. 3. 

Thecocarpus perarmatus. – Billard 1913: 95, figs 81–86. 


Kei Islands Expedition stations: 53, with corbulae. – 54, with 

corbulae.


Fig. 78. Lytocarpia perarmata (Billard, 1908); station 53. A. Colony silhouette. B. Hydrotheca in side view. C. Hydrocladium 

seen from behind, note asymmetric pair of lateral nematothecae (top), and additional nematotheca on rear side (below), same 

scale as B. D. Part of corbula. E. Appendage at base of hydrocladium. – Scales: A = 1 cm; B–C = 0.1 mm; D = 0.5 mm; 

E = 0.2 mm. 

Description 

Colonies pinnate, 4–6 cm high, planar, stem not 

forking, lightly polysiphonic but becoming monosiphonic 

towards distal, composed of a superficial 

primary tube and a few auxiliary tubes. 

Primary tube with nematothecae and apophyses 

for the hydrocladia. Hydrorhiza a tangled mass of 

stolons anchoring colony in soft substrate. 

Hydrocladia, alternate, long (up to 2.5 cm), 

straight, with oblique nodes, nodes can be indistinct. 

Hydrotheca cup-shaped, depth 0.3 mm, 

slightly curved, opening-plane perpendicular to 

hydrocladial axis, abcauline wall rounded, short 

intrathecal shelf on adcauline side, hydrothecal 

rim with one median, rectangular tooth, this tooth 

slightly gutter-shaped, lateral rim of hydrotheca 

with two or more shallow teeth. 

Median inferior nematotheca gutter-shaped, 

attached up to middle of hydrotheca and more, 

without foramen leading into hydrotheca. Lateral 

pair of nematothecae unequal, one nematotheca 

taller and displaced towards rear side. On rear 

side at the level of lower third of hydrotheca an 

239 

additional nematotheca, displaced from median 

line towards side with smaller lateral nematotheca. 

Hydrocladial apophysis of primary tube often 

bearing a flexible appendage consisting of a row 

of segments with nematothecae, each segment 

with three nematothecae (Fig. 78E). 

Gonothecae protected in corbulae. Corbula 

replacing a hydrocladium, long and thin, tubular, 

about 1/3 of hydrocladial length, beginning with 

a few (3) segments having a structure identical to 

normal hydrocladia (Fig. 78D), then with two 

rows of costae forming a closed corbula. Costae 

flattened, fused at distal end with opposite costae, 

one row of tubular nematothecae along distal rim 

of each costa, each costa at its base with a lobe 

bearing a fully formed hydrotheca. 

Remarks 

Because Lytocarpia Kirchenpauer, 1872 has priority 

over its synonym Thecocarpus Nutting, 

1900 (Rees & Vervoort 1987), Thecocarpus perarmatus 

is here used in the new combination 

Lytocarpia perarmata.

240 

With its additional nematotheca placed almost 

behind the hydrotheca and the asymmetric lateral 

nematothecae, this species is very distinct and 

easy to recognize, but see also the discussion 

under L. orientalis. 

The apophyses of the primary tube that bear 

the hydrocladia often also possess an appendage 

resembling the pseudophylactocarps described 

for Gymnangium longicorne, Lytocarpia angulosa 

and other aglaophenids (Fig. 78E). Although 

it is likely a modified hydrocladium, it is 

probably not strictly homologous to the pseudophylactocarps 

of Gymnangium longicorne, 

because it does not replace a hydrocladium. 

Distribution 

Indonesia. Type localities: 2.475°S, 131.058°E, 

188 m and 2.592°S, 131.437°E, 95 m. 

Lytocarpia orientalis (Billard, 1908) n. comb., 

n. status 

Fig. 79. 

Thecocarpus myriophyllum var. orientalis Billard, 1908a: 

73, fig. 1. – Billard 1913: 91, fig. 76–78, pl. 5: fig. 43. – 

Jäderholm 1919: 25, pl. 6: fig. 5. – Billard 1922: 347, fig. 

2. – Vervoort 1941: 23. – Vervoort 1972: 221, fig. 76. 

Thecocarpus myriophyllum var. angulatus Billard, 1913: 

94, figs 79–80. – Billard 1922: 347, fig. 3. 

Thecocarpus myriophyllum var. elongatus Billard, 1910: 51. 

– Billard 1922: 348, fig. 4. 

Gymnangium unjinense Watson, 2000: 62, fig. 50A–E, new 

synonym. 


Kei Islands Expedition stations: 67. – 72, with corbulae. – 

90, with corbulae. – 106. 

Description 

Colonies pinnate, stems never forked, up to 12 

cm high, outline of plume with blunt top. Hydrorhiza 

a tangled mass of stolons anchoring 

colony in sediment. Stem polysiphonic, becoming 

monosiphonic in distal-most part, in basal 

part pinched obliquely one or more times; stem 

composed of a superficial primary tube on a 

bundle of auxiliary tubes. Auxiliary tubes with 

rows of small, ovoid nematothecae along the 

grooves where two tubes meet. Primary tube with 

more or less distinct nodes, each segment with 

one hydrocladial apophysis and two nematothecae: 

one on lower part, one axillary; mamelon on 

P. SCHUCHERT 

apophysis present. Pseudophylactocarps absent. 

Hydrocladia dense, straight, stiff, up to 2 cm 

long, regularly segmented by slightly oblique 

nodes, each segment with hydrotheca covering 

about ¾ of segment and three nematothecae, 

internal ribs weakly developed or absent. 

Hydrotheca 0.21–0.28 mm deep, opening diameter 

0.2 mm, cup-shaped, abcauline wall gently 

convex, adcauline wall completely adnate, 

opening-plane nearly perpendicular to hydrocladium 

or inclined towards below, hydropore in 

about middle of adcauline wall, covered by a 

downward pointing intrathecal septum attached 

at adcauline wall, septum margin thickened, septum 

makes completely contracted hydranth to 

face downward. Abcauline margin with a distinct 

median cusp, cusp depressed longitudinally and 

thus gutter-shaped; lateral margin with 2–3 shallow, 

variable teeth. 

Median inferior nematotheca almost completely 

adnate, attached along 6/7 of abcauline 

wall of hydrotheca, free end short, gutter-shaped, 

reaching to rim of hydrotheca, without foramen 

into hydrotheca. Lateral nematothecae cupshaped, 

opening facing towards above. 

Gonothecae in corbulae, corbula replaces hydrocladium. 

Corbula thin, closed, about 7 mm 

long, diameter 0.7 mm; first three segments identical 

to hydrothecate segments of normal hydrocladia, 

then axis furnished with two rows of 

costae, costae fused together to form an almost 

closed tube; near base of each costa a nematotheca 

and a free hydrotheca with its lateral nematothecae; 

instead of median inferior nematotheca 

grows the leaf-like main body of the costa with 

one row of about 4 nematothecae along edge 

facing away from stem. Tip of corbula axis (rachis) 

with short process bearing nematothecae. 

The pair of lateral nematothecae of the costal 

hydrotheca can be replaced by a process bearing 

4–7 nematothecae, rarely this process developed 

as a free costa. The most proximal costae can be 

free. 

Remarks 

Lytocarpia orientalis (Billard, 1908) was first 

described as a variant orientalis of the Atlantic L. 

myriophyllum (Linnaeus, 1758). Billard also described 

several other variants of this species and


Fig. 79. Lytocarpia orientalis (Billard, 1908); station 72. A. Colony silhouette. B. Segment of primary tube. C. Hydrocladial 

segment from side. D. Middle part of corbula. – Scales: A = 1 cm; B = 0.1 mm; C = 50 µm; D = 0.2 mm. 

he reviewed their features (Billard 1922). Lytocarpus 

myriophyllum (Linnaeus, 1758) is indeed 

a very variable species as far as the hydrotheca 

and the colony form are concerned. Ramil & 

Vervoort (1992) and also Ansìn Agìs, Ramil 

& Vervoort (2001) documented thoroughly the 

variation of the hydrotheca of a population from 

the north-eastern Atlantic. Atlantic and Mediterranean 

colonies can be either simple or branched, 

reaching heights of up to 1 m. The variation of the 

hydrothecal morphology and colony form observed 

in the Atlantic populations also encompass 

the variant orientalis, and both morphotypes 

cannot objectively be separated using this character 

set alone. Constant differences between the 

Atlantic and Pacific populations were, however, 

observed in the morphology of the corbulae. 

While Atlantic morphotypes have open corbulae 

with isolated, thin costae, the ones from the Pacific 

have closed, tubiform corbulae formed by 

the fusion of leaf-like costae (compare Figs 79D 

and 80, note different scaling factor). There is 

241 

also a considerable size difference. Whether 

these differences are due to inter- or intra specific 

variation is not immediately apparent, and 

whether the Pacific morphotype corresponds to a 

true geographic subspecies of L. myriophyllum or 

whether it represents a separate species can only 

be answered based on genetic information (note 

that the category subspecies is only used in some 

species concepts, while others do not accept 

them, see Wheeler & Meier 2000). In other aglaophenids, 

however, such a difference in corbula 

morphology is seen as a good indicator for two 

species being involved (cf. L. delicatula and L. 

phyteuma). Additionally, the wide geographic 

separation – Northern Atlantic Ocean versus Pacific 

Ocean – argues in favour of treating the 

two morphotypes as representatives of separate 

species. Therefore, and out of a preference for 

species concepts not accepting the category of 

subspecies, Billard’s variety orientalis is raised 

to full species level as Lytocarpia orientalis 

(Lytocarpia has priority over Thecocarpus, see

242 

Fig. 80. Lytocarpia myriophyllum (Linnaeus, 1758); Azores, 

Atlantic Ocean (MHNG collection). Part of corbula with two 

costae. – Scale: 0.5 mm. 

above). Contrary to Billard (1913), the present 

Indonesian material was very homogeneous and 

showed only little variation. This material thus 

differed also from Atlantic L. myriophyllum (see 

Cornelius 1995b, Schuchert 2001) in having 

unbranched colonies only, having a median 

nematothecae reaching higher up the abcauline 

wall of the hydrotheca, having much smaller 

hydrothecae, and lacking intra-segmental ribs. 

Thecocarpus myriophyllum var. angulatus 

Billard, 1913 differs from the variety orientalis 

mainly in having more inclined hydrothecal 

openings. This difference and others mentioned 

by Billard (1913) appear insignificant and this 

form is here regarded as a synonym only. 

Likewise, Thecocarpus myriophyllum var. 

elongatus Billard, 1910 is also seen as a synonym 

of L. orientalis (see Billard 1922). 

According to Ansìn Agìs, Ramil, & Vervoort 

(2001: 98), Thecocarpus myriophyllum vervoorti 

Stepanjants, 1979 from the south tip of South 

America also belongs to the orientalis group. The 

spine-like processes of the corbula depicted in 

Stepanjants (1979) set this species somewhat 

apart. Because of this, the wide geographic separation 

and its occurrence in colder waters it is 

here not included in the synonymy, pending 

closer examination of material. 

Lytocarpia annandalei (Ritchie, 1910a) also 

resembles L. orientalis, but the former has 

pseudophylactocarps (Ritchie interpreted them 

P. SCHUCHERT 

as phylactocarps). Pseudophylactocarps have so 

far never been observed in L. orientalis, but they 

occur in L. perarmata. The latter species is – 

apart from the pseudophylactocarps and the additional 

nematotheca behind the hydrotheca – 

strikingly similar to L. orientalis, notably in 

colony habit and hydrothecal morphology. 

Gymnangium unjinense Watson, 2000 appears 

identical to the present material and this 

name is here regarded as a subjective synonym of 

L. orientalis. Watson (2000) based her description 

on infertile material and acknowledged the 

similarity to M. orientalis. The differences given 

by Watson are here considered as not significant 

Distribution 

Indonesia (Billard 1913), Philippines (Billard 

1910, as L. myriophyllum var. elongata), Japan 

(Jäderholm 1919), Chile (Vervoort 1972), northern 

Australia (Watson 2000, as Gymnangium 

unjinense). Perhaps also China Sea (Leloup 

1937, cited in Ansìn Agìs, Ramil, & Vervoort 

2001). Type localities: Borneo Bank, SW Celebes, 

5.058°S, 119.000°E, 450 m and Waigeu 

Island, NW New Guinea, 0.063°N, 130.405°E, 

141 m. 

Aglaophenia cupressina Lamouroux, 1816 

Fig. 81. 

Aglaophenia cupressina Lamouroux, 1816: 169. – Kirchenpauer 

1872: 27, pl. 1: fig. 11. – Billard 1907: 331, fig. 5. 

– Billard 1909: 330. – Billard 1913: 107, fig. 96; pl. 6. – 

Bale 1915: 319, pl. 47: figs 6–8. – Leloup 1930b: 15, figs 

10–11, pl. 2: fig. 4. – Leloup 1932: 1–3. – Vervoort 1941: 

233, fig. 11. – Millard & Bouillon 1974: 36, fig. 8E–F. – 

Millard 1975: 408, fig. 128A–C. 

Plumularia bipinnata Lamarck, 1816: 126. – Billard 1907: 

331. 

Aglaophenia macgillivrayi Busk, 1852: 400. – Allman 

1883: 34, pl. 10, pl. 20: figs. 4–6. – von Campenhausen 

1896b: 315. – Billard 1909: 331. 

Aglaophenia spicata. – Kirchenpauer 1872; 27, pl. 1: fig. 12, 

pl. 2: fig. 11, pl. 4: fig. 11. [Not Aglaophenia spicata 

Lamouroux, 1816 = Monoserius pennarius (Linnaeus, 

1758)] 

Corbulifera macgillivrayi. – Naumov 1969: 530, figs 380– 

381. 


Kei Islands Expedition, Kei Islands, Tual, 2 m, 21 Mar 1922, 

numerous stems, with corbulae. – Kei Islands Expedition, 

Moluccas, Bay of Ambon, 1 m, 8 Feb 1922, with corbulae. – 

Kei Islands Expedition, Banda Islands, Neira Island, 10 m, 5


Fig. 81. Aglaophenia cupressina Lamouroux, 1816; A–C, Bay of Ambon, 1 m depth; D–F, Neira Island, 10 m depth. A. Colony 

silhouette. B. Hydrocladial segment. C. Two costae of a male corbula. D. Colony silhouette, same scale as A. E. Hydrocladial 

segment, same scale as B. F. Two costae of a female corbula, same scale as C. – Scales: A, D = 2 cm; B, E = 0.1 mm; C, F = 

0.2 mm. 

Jun 1922, numerous stems, with corbulae. – Kei Islands 

Expedition, Kei Islands, Tual, 1–2 m, 23 Mar 1922, with 

corbulae. 

Description 

Colonies large, 7–20 cm, branched up to fourth 

order, branching often in one plane, usually a 

243 

thick central primary axis (stem) with two lateral 

rows of side-branches, side-branches nearly 

opposite, regularly spaced, some side-branches 

branched again similar to main axis. Main stem 

and all branches thickly polysiphonic, only very 

short stretches at distal ends monosiphonic, polysiphonic 

parts composed of a superficial pri-

244 

mary tube and a bundle of auxiliary tubes. Primary 

tube of side-branches originate from primary 

tube of stem, branching points of primary 

tubes often overgrown by few auxiliary tube. 

Primary tubes segmented in terminal parts, each 

segment with an apophysis for hydrocladium and 

two nematothecae at side of apophysis. Primary 

tubes usually with hydrocladia, but these may be 

broken off in proximal part of stem. Stolons 

tangled, creeping, anchoring colony on solid 

substrata. Inside of periderm of whole colony 

densely covered by a lining of spherical zooxanthellae, 

size 7–9 µm. 

Hydrocladia alternate, thick and bristly, making 

colony resemble a fir twig, hydrocladia 3–5 

mm, 6–11 hydrothecae, length within one colony 

similar, flattened laterally, rear side keeled, regularly 

segmented by transverse nodes, each segment 

with one hydrotheca, with two strong internal 

ribs (ridges, thickenings) at the level of the 

hydrotheca, these ribs irregularly curved, fused 

to a longitudinal ridge running along rear side, 

rear wall otherwise remarkably thin. 

Hydrotheca relatively narrow, depth 0.25– 

0.28 mm, diameter 0.13–0.15 mm, campanulate, 

not curved, adcauline side completely adnate, 

opening slightly inclined towards below (approx. 

30°), lateral margin slightly undulated or with a 

distinct antero-lateral cusp, hydropore at base of 

rear wall, above hydropore a very short adcauline 

shelf which is continued as a transverse internal 

ridge, presence variable. 

Median inferior nematotheca very stout, 

breadth in lateral view 2/3 or more of hydrothecal 

diameter, completely adnate, reaching to the 

level of hydrotheca, margin with two broad lateral 

cusps (or free end gutter-shaped), on inside 

near upper third an oblique septum with a pore on 

adcauline side; no foramen into hydrotheca. Lateral 

nematotheca overtop hydrotheca, ovoid to 

cup shaped, about half as high as hydrotheca, 

opening directed towards above or inclined towards 

rear. 

Gonothecae in closed corbula which replaces 

a hydrocladium. Corbula 1.7–2.5 mm long, tubular, 

first segment like in ordinary hydrocladia, 

then with leaf-like costae, 5–8 per side, fused to 

form a cylinder but with slit-like lateral openings, 

costae with one row of nematothecae, basal 2–3 

may be on a raised lobe. 

P. SCHUCHERT 

Remarks 

The samples from 1 m and 10 m water depth 

showed very obvious differences that are very 

likely attributable to their different environment 

(cf. Fig. 81A–C and 81D–F). The colonies from 

10 m depth were dark brown, while those from 

1 m were bright amber coloured. Furthermore, 

the colonies from 10 m were more branched, 

more flexible, less bristly, had longer and thinner 

hydrocladia. There was also a difference in the 

corbulae. This difference, however, could be either 

due to depth or sexual dimorphism. The 

limited number of independent colonies did not 

make it possible to draw a reliable conclusion. 

The difference was mainly confined to the presence 

or absence of a raised lobe near the base of 

each costa. This lobe had 2–3 nematothecae. The 

opening behind this lobe was also larger than the 

usual slits. In the examined material this type of 

corbula contained gonothecae with eggs, while 

the other type of corbula was quite certainly 

male. Both type of corbulae have been described 

by other authors. Billard (1913) depicts the form 

without lobe, while Millard & Bouillon (1974) 

depict a corbula with a basal lobe. Bale (1915) 

also described such a lobe and he also thought of 

a possible sexual dimorphism. 

Aglaophenia cupressina is a very characteristic 

species and especially the microscopic structure 

make its identification easy (see Fig. 81B 

and 81E). The colonies often occur in very shallow 

waters and are thus easily encountered. They 

are very notorious for their painful stings. 

Naumov (1969, as Corbulifera macgillivrayi) 

reported this otherwise tropical shallow water 

species from the arctic sea of Okhotsk and from 

deep waters near the Kuriles. His material was 

sterile. For biogeographic reasons I doubt somewhat 

that Naumov’s specimen belonged to A. 

cupressina, although his figures look identical to 

the present material. Although A. cupressina is 

widespread in the tropical Indo-Pacific, interestingly, 

it is not known to occur on smaller islands 

of the tropical Pacific (Polynesia). 

Distribution 

From Zanzibar and Mozambique to Great Barrier 

Reef, Indonesia, New Guinea, Philippines, Japan. 

?Sea of Okhotsk. Occurs even in very shal-


low water (1 m), but Billard (1913) found it down 

to 564 m. Type locality: East Indies (Lamouroux, 

1816). 

Aglaophenia sibogae Billard, 1913, n. status 

Fig. 82. 

Aglaophenia pluma var. sibogae Billard, 1913: 101, figs 90– 

91. 


Kei Islands Expedition station 65, one plume, with corbulae. 

Description 

Colony pinnate, 3 cm high; stolons creeping; 

stem with prosegment, monosiphonic, with oblique 

hinge-joint, with regular nodes, segments 

with hydrocladial apophysis bearing a mamelon 

and three nematothecae: two on each side of the 

apophysis and one below. 

Hydrocladia alternate, thin and flexible, up to 

4 mm, regularly segmented by slightly oblique 

nodes, segments without internal ribs. 

Hydrothecal walls U-shaped in side view, 

depth 0.30–0.35 mm, adcauline wall not entirely 

adnate, free for about 1/7 of total abcauline 

length, hydropore close to base, diameter of 

opening 0.15–0.17 mm, opening slightly inclined 

towards below, margin with 9–10 sinusoid 

cusps: one median abcauline (largest), four 

laterals, and sometimes a shallow and broad 

adcauline one (the latter can be absent). 

Median inferior nematotheca nearly completely 

adnate, tip reaching to base of abcauline 

cusp, free part about 1/7 of length, gutter-shaped, 

with foramen leading into hydrotheca, perisarc of 

outer wall thickened where nematotheca joins 

internode. Lateral nematothecae ovoid to cupshaped, 

reaching just below tips of marginal 

cusps, height relatively small (60 µm high), inner 

wall reduced. 

Gonothecae protected in corbulae. Corbula 

open, replacing a hydrocladium, shorter than 

hydrocladium, first segment identical to the ones 

of normal hydrocladia, followed by rachis bearing 

two rows of alternate costae, about 8 per side; 

costae rod-shaped, free, with two rows of lateral 

nematothecae and an additional one in axil to 

rachis. Gonothecae oblong, about 0.6 mm. 

245 

Fig. 82. Aglaophenia sibogae Billard, 1913. A. Colony 

silhouette. B. Stem segment. C. Two hydrocladial segments. 

D. Hydrotheca seen from abcauline side, same scale as B. E. 

Corbula in side view, only one row of costae shown. – 

Scales: A = 1 cm; B, C = 0.1 mm; E = 0.4 mm 

.

246 

Remarks 

Aglaophenia sibogae Billard, 1913 was first described 

as a variety of A. pluma (Linnaeus, 1758). 

Aglaophenia pluma is a species of the temperate 

north-eastern Atlantic, but it also penetrates 

into the western Mediterranean (Svoboda & 

Cornelius 1991). It always has closed corbulae 

and can also form branched colonies. Billard’s 

Indonesian variant has open corbulae and referring 

to the same arguments as given for Lytocarpia 

orientalis (see above) it is here raised to 

full species level. 

Aglaophenia sibogae resembles closely A. 

postdentata Billard, 1913 (for description see 

also Millard & Bouillon 1973, Ryland & Gibbons 

1991, Watson 1994). Billard (1913) distinguished 

A. postdentata on account of the smaller 

hydrothecae (depth 0.22–0.24 mm) and the presence 

of a distinct cusp on the adcauline side of the 

hydrothecal opening. The colony size of A. postdentata 

does also not surpass 1 cm, while the 

stems of Aglaophenia sibogae are more than two 

times as high. There seem to be no significant 

differences in the morphology of the corbulae. 

Perhaps when more material of both species becomes 

available, intermediate forms might link 

the two morphotypes and A. sibogae could be 

prove to be conspecific with A. postdentata. 

Distribution 

Indonesia. Type localities: 3°27’S, 117°36’E, 59 

m; 1°42.5’S, 130°47.5’E, 32 m (Indonesia). 

ACKNOWLEDGEMENTS 

I wish to thank Dr. Ole Tendal of the Zoological 

Museum, University of Copenhagen, for his offer 

to study Mortensen’s hydroids, the loan of 

other hydroids, and also for his hospitality during 

two pleasant stays in Copenhagen. I would also 

like to thank Dr J. Watson for reading and correcting 

the manuscript and for her valuable comments 

that improved the quality of this report. 

The loans of hydroids from the NMNH, the Museum 

of Victoria, and the ZMA helped to settle 

many critical details and the generosity of these 

museums is highly appreciated. 

P. SCHUCHERT 

REFERENCES 

Allman, G. J. 1876. Diagnoses of new genera and species of 

Hydroida. – Journal of the Linnean Society of London. 

(Zoology) 12: 251–284, pls 9–23. 

Allman, G. J. 1877. Report on the Hydroida collected during 

the Exploration of the Gulf Stream by L. F. de Pourtalès, 

Assistant United States Coast Survey. – Memoirs of the 

Museum of Comparative Zoology 5: 1–66, pls 1–34. 

Allman, G. J. 1883. Report on the Hydroida dredged by 

H. M. S. Challenger during the years 1873–76. – The 

Voyage of H. M. S. Challenger, Zoology 20: 1–55, pls 1– 

20. 

Allman, G. J. 1886. Description of Australian, Cape and 

other Hydroids, mostly new, from the collection of Miss 

H. Gatty. – Journal of the Linnean Society 19: 132–161. 

Allman, G. J. 1888. Report on the Hydroida dredged by H. 

M. S. Challenger during the years 1873–76. Part II. - The 

Tubularinae, Corymorphinae, Campanularinae, Sertularinae, 

and Thalamophora. – The Voyage of H. M. S. 

Challenger, Zoology 23: 1–90. 

Ansín Agís, J., F. Ramil, & W. Vervoort. 2001. Atlantic 

Leptolida (Hydrozoa, Cnidaria) of the families Aglaopheniidae, 

Halopterididae, Kirchenpaueriidae and Plumulariidae 

collected during the CANCAP and Mauretania-II 

expeditions of the National Museum of Natural 

History, Leiden, the Netherlands. – Zoologische Verhandelingen, 

Leiden 333: 1–268. 

Bale, W. M. 1884. Catalogue of the Australian Hydroid 

Zoophytes. – Australian Museum Catalogue No. 8, 198 

pp, 19 pls. 

Bale, W. M. 1888. On some new and rare Hydroida in the 

Australian Museum collections. – Proceedings of the 

Linnean Society of New South Wales 3: 745–799, pls 

12–21. 

Bale, W. M. 1913. Further notes on Australian hydroids. II. 

– Proceedings of the Royal Society of Victoria (new 

series) 26: 114–147, pls 12–13. 

Bale, W. M. 1914a. Report on the Hydroida collected in the 

Great Australian Bight and other localities. Part 1. – 

Biological Results of the Fishing Experiments carried on 

by the F.I.S. “Endeavour,” 1909–1914 2: 1–62, pls 1–7. 

Bale, W. M. 1914b. Report on the Hydroida collected in the 



by the F.I.S. “Endeavour”, 1909–1914 2: 164–188, pls 

35–38. 

Bale, W. M. 1914c. Further notes on Australian hydroids. III. 

– Proceedings of the Royal Society of Victoria, n. ser. 27: 

72–93, pls 11–13. 

Bale, W. M. 1915. Report on the Hydroida collected in the 



by the F.I.S. “Endeavour,” 1909–1914 3: 241–336, pls 

46–47. 

Bale, W. M. 1919. Further notes on Australian hydroids. IV. 

– Proceedings of the Royal Society of Victoria (new 

series) 31: 327–361, pls 16–17. 

Bale, W. M. 1924. Report on some hydroids from the New 

Zealand coast, with notes on New Zealand Hydroida 

generally, supplementing Farquhar’s list. – Transactions


and Proceedings of the New Zealand Institute 55: 225– 

268. 

Bedot, M. 1893–1909. Voyage Scientifique dans l’Archipel 

Malais. – W. Kündig, Genève, 558 pp., 31 pls. 

Billard, A. 1904. Hydroides récoltés par M. Ch. Gravier dans 

le Golfe de Tadjourah. – Bulletin du Muséum national 

d’Histoire naturelle de Paris 11: 480–485. 

Billard, A. 1905. Hydroides récoltés par M. Seurat aux Îles 

Gambier. – Bulletin du Muséum national d’Histoire naturelle, 

Paris 5: 331–334. 

Billard, A. 1907a. Hydroides de Madagscar et du su-est de 

l’Afrique. – Archives de Zoologie Expérimentale et Générale 

7: 335–396. 

Billard, A. 1908a. Note sur deux varietés nouvelles d’Hydroides 

provenant de l’expedition du “Siboga”. – Archives 

de Zoologie Expérimentale et Générale (4) 8, 

Notes et Revue: LXXIII–LXXVII. 

Billard, A. 1908b. Note sur une variété nouvelle d’Hydroide. 

– Archives de Zoologie Expérimentale et Générale (4) 8, 

Notes et Revue: CXII–CXIV. 

Billard, A. 1908c. Sur les Plumulariidae de la collection du 

Challenger. – Comptes rendus hebdomadaires des séances 

de l’Académie des sciences de Paris 147: 758–760, 

938–941. 

Billard, A. 1909. Révision des espèces types d’hydraires de 

la collection Lamouroux. – Annales des Sciences naturelles, 

neuvième série, Zoologie 9: 307–336. 

Billard, A. 1910. Révision d’une partie de la collection du 

British Museum. – Annales des Sciences naturelles, neuvième 

série, Zoologie 11: 1–67. 

Billard, A. 1911a. Note sur un nouveau genre et une nouvelle 

espèce d’Hydroïde: Sibogella erecta. – Archives de Zoologie 

Expérimentale et Générale (5) 6, Notes et Revue: 

CVIII–CIX. 

Billard, A. 1911b. Note préliminaire sur les espèces nouvelles 

de Plumulariidae de l’expédition du “Siboga”. – 

Archives de Zoologie Expérimentale et Générale (5) 8, 

Notes et Revue: LXII–LXXI. 

Billard, A. 1913. Les Hydroides de l’expédition du SIBO- 

GA. I Plumulariidae. – Siboga Expeditie 7a: 1–115, pls 

1–6. 

Billard, A. 1918. Notes sur quelques espèces d’hydroïdes de 

l’expédition du Siboga. – Archives de Zoologie Expérimentale 

et Générale 57, Notes et Revue: 21–27. 

Billard, A. 1919a. Note sur une espèce nouvelle d’hydroïde 

gymnoblastique (Clava krempfi), parasite d’un Alcyonaire. 

– Bulletin du Muséum national d’Histoire naturelle 

de Paris 25: 187–188. 

Billard, A. 1919b. Note sur quelques espèces nouvelles de 

Sertularella de l’expédition de “Siboga”. – Archives de 

Zoologie Expérimentale et Générale 58, Notes et Revue: 

18–23. 

Billard, A. 1920a. Note sur une espèce nouvelle d’Hydroïde: 

Sertularella singularis. – Archives de Zoologie Expérimentale 

et Générale 59, Notes et Revue: 14–16. 

Billard, A. 1920b. Notes sur quatres espèces d’hydroides du 

genre “Diphasia”. – Bulletin du Muséum national d’Histoire 

naturelle de Paris 45: 144–147. 

Billard, A. 1922. Le Thecocarpus myriophyllum et ses variétés. 

– Annales Sciences naturelles, séries Botanique et 

Zoologie, 10e sér. 5: 343–350. 

247 

Billard, A. 1924. Note critique sur divers genres et espèces 

d’hydroides avec la description de trois espèces nouvelles. 

– Revue suisse de Zoologie 31: 53–74. 

Billard, A. 1925a. Note sur quelques espèces la plupart 

nouvelles de synthécides et de sertularides du Siboga. – 

Bulletin de la Société Zoologique de France 49: 646– 

652. 

Billard, A. 1925b. Les hydroïdes de l’expédition du Siboga. 

II. Synthecidae et Sertularidae. – Siboga Expeditie 7b: 

117–232. 

Billard, A. 1929a. Note sur deux espèces d’halécide du genre 

Diplocyathus Allm. – Bulletin de la Société Zoologique 

de France 54: 69–71. 

Billard, A. 1929b. Sur l’identité des genres Sibogella et 

Stechowia (Plumulariidae). – Bulletin de la Société Zoologique 

de France 54: 72–73. 

Billard, A. 1929c. Note sur un genre nouveau et quelques 

espèces nouvelles d’Halecidae. – Bulletin de la Société 

Zoologique de France 54: 305–307. 

Billard, A. 1930. Note sur une espèce nouvelle d’hydroïde 

(Thyroscyphus sibogae). – Bulletin de la Société Zoologique 

de France 55: 230–232. 

Billard, A. 1933. Les hydroïdes des golfes de Suez et 

d’Akaba. – Mémoires de l’Institut d’Egypte 21: 1–30, pl. 

1. 

Billard, A. 1937. Note sur une nouvelle espèce de Halecium 

(Halecium galeatum). – Bulletin de la Société Zoologique 

de France 62: 292–293. 

Billard, A. 1938. Note sur une espèce de campanularidés 

(Clytia Gravieri Billard). – Bulletin du Muséum d’Histoire 

naturelle de Paris, 2ème sér. 10: 429–432. 

Billard, A. 1939. Note sur le Sertularella tricincta n. sp. – 

Bulletin de la Société Zoologique de France 64: 248– 

250. 

Billard, A. 1940a. Note sur une espèce nouvelle d’hydroïde: 

Egmundella sibogae (Campanulinidae). – Bulletin de la 

Société Zoologique de France 5: 134–135. 

Billard, A. 1940b. Note sur deux espèces nouvelles de 

Campanulinidae (hydroïdes). – Bulletin de la Société 


Billard, A. 1941a. Note sur les hydroïdes: Hebella costata 

(Bale) et H. corrugata (Thornely). – Bulletin de la Société 


Billard, A. 1941b. Note sur une espèce d’hydroïde peu 

connue: Stegopoma operculatum (Nutting). – Bulletin de 

la Société Zoologique de France 66: 16–17. 

Billard, A. 1942a. Note sur une nouvelle espèce et une 

nouvelle variété de Zygophylax (hydroïdes). – Bulletin 

de la Société Zoologique de France 67: 34–36. 

Billard, A. 1942b. Note sur quelques espèces et variétés 

nouvelles des genres Hebella et Hebellopsis (hydroïdes). 

– Bulletin de la Société Zoologique de France 67: 67–70. 

Boero, F. 1981. Systematics and ecology of the hydroid 

population of two Posidonia oceanica Meadows. – Marine 

Ecology 2: 181–197. 

Boero, F., & J. Bouillon. 1989. An evolutionary interpretation 

of anomalous medusoid stages in the life cycles of 

some Leptomedusae (Cnidaria). – European Marine Biology 

Symposium 23: 37–41. 

Boero, F., & M. Sarà. 1987. Motile sexual stages and evolu-

248 

tion of Leptomedusae (Cnidaria). – Bollettino di Zoologia 

54: 131–139. 

Boero, F., J. Bouillon, & N. Gravier-Bonnet. 1995. The life 

cycle of Pteroclava krempfi (Cnidaria, Hydrozoa, Cladocorynidae), 

with notes on Asyncoryne philippina (Asyncorynidae). 

– Scientia Marina 59: 65–76. 

Boero, F., J. Bouillon, & S. Kubota. 1997. The medusae of 

some species of Hebella Allman, 1888, and Anthohebella 

gen. nov. (Cnidaria, Hydrozoa, Lafoeidae), with a 

world synopsis of species. – Zoologische Verhandelingen, 

Leiden 310: 1–53. 

Borradaile, L. A. 1905. Hydroids. – The fauna and geography 

of the Maldive and Laccadive Archipelagos 2: 

836–845. 

Bosc, L. A. G. 1802. Histoire naturelle des vers, contenant 

leur description et leurs moeurs; avec figures dessinées 

d’après nature. Tome 3. – Guilleminet, Paris, 270 pp., 

pls. 26–32. 

Boschma, H. 1953. The Stylasterina of the Pacific. – Zoologische 

Meddeligen, Leiden 32: 165–184. 

Boschma, H. 1956. Milleporina and Stylasterina. In: R. C. 

Moore (ed). Treatise on Invertebrate Paleontology, part 

F, Coelenterata. University of Kansas Press, Kansas, pp. 

F99–F106. 

Boschma, H. 1957. List of the described species of the 

Stylasterina. – Zoologische Verhandelingen, Leiden 33: 

1–72. 

Bouillon, J. 1978a. Hydroméduses de l’archipel des Sechelles 

et du Moçambique. – Revue de Zoologie Africaine 

92: 117–172. 

Bouillon, J. 1978b. Hydroméduses de la mer de Bismarck 

(Papouasie, Nouvelle-Guinée). Partie 1: Anthomedusae 

Capitata (Hydrozoa – Cnidaria). – Cahiers de Biologie 

Marine 19: 249–297. 

Bouillon, J. 1980. Hydroméduses de la Mer de Bismarck. 

(Papouasie Nouvelle-Guinée). Partie 3: Anthomedusae - 

Filifera (Hydrozoa – Cnidaria). – Cahiers de Biologie 

Marine 21: 307–344. 

Bouillon, J. 1984a. Revision de la famille des Phialuciidae 

(Kramp, 1955) (Leptomedusae, Hydrozoa, Cnidaria), 

avec un essai de classification des Thecatae-Leptomedusae. 

– Indo-Malayan Zoology 1: 1–24. 

Bouillon, J. 1984b. Hydroméduses de la Mer de Bismarck 

(Papouasie Nouvelle-Guinée). Partie 4: Leptomedusae 

(Hydrozoa – Cnidaria). – Indo-Malayan Zoology 1: 25– 

112. 

Bouillon, J. 1985a. Essai de classification des hydropolypeshydroméduses 

(Hydrozoa – Cnidaria). – Indo-Malayan 

Zoology 2: 29–243. 

Bouillon, J. 1985b. Notes additionelles sur les hydroméduses 

de la mer de Bismarck (Hydrozoa – Cnidaria). – 

Indo-Malayan Zoology 2: 245–266. 

Bouillon, J., F. Boero, & G. Seghers. 1987. Redescription of 

Cladocoryne haddoni Kirkpatrick and a proposed phylogeny 

of the superfamily Zancleoidea (Anthomedusae, 

Hydrozoa, Cnidaria). – Indo-Malayan Zoology 4: 279– 

292. 

Bouillon, J., K. Wouters, & F. Boero. 1992. Étude des 

Solanderiidae de la Baie de Hansa (Papouasie Nouvelle- 

Guinée) avec une révision du genre Solanderia (Cni- 

P. SCHUCHERT 

daria, Hydrozoa. – Bulletin de l’Institut Royal des Sciences 

Naturelles de Belgique, Biologie 62: 5–33. 

Briggs, E. A. 1922. Description of the coppinia of an Australian 

hydroid. – Australian Zoologist 2: 148–150. 

Brinckmann, A. 1959. Ueber den Generationswechsel von 

Eucheilota cirrata (Haeckel, 1879). – Pubblicazioni della 

Stazione Zoologica di Napoli 31: 82–89. 

Brinckmann-Voss, A. 1970. Anthomedusae/Athecata (Hydrozoa, 

Cnidaria) of the Mediterranean. Part I. Capitata. 

– Fauna e Flora Golfo di Napoli 39: 1–96, pls 1–11. 

Broch, H. 1918. Hydroida. (Part II). – Danish Ingolf Expedition 

5: 1–206. 

Broch, H. 1936. Untersuchungen an Stylasteriden (Hydrokorallen). 

Teil I. – Skrifter utgitt av det Norske Videnskaps-Akademi 

i Oslo, I. Mat. -naturv. Klasse 1936 (8): 

1–103, pls 1–13. 

Busk, G. 1852. An account of the Polyzoa, and the sertularian 

zoophytes, collected in the voyage of “Rattlesnake”, 

on the coasts of Australia and the Louisiade 

Archipelago, etc. – Pp. 343–402 in: J. MacGillivray, 

Narrative of the voyage of H.M.S. Rattlesnake, commanded 

by late Captain Owen Stanley, R.N., F.R.S., etc., 

during the years 1846–1850. Vol 1. Appendix 4. – T. and 

W. Boone, London. 

Cairns, S. D. 1983. Pseudocrypthelia, a new genus of stylasterine 

coral (Coelenterata: Hydrozoa) from the Indonesian 

region. – Beaufortia 33: 29–35. 

Cairns, S. D. 1991. The marine fauna of New Zealand: 

Stylasteridae (Cnidaria: Hydroida). – New Zealand Oceanographic 

Institute Memoir 98: 1–179. 

Cairns, S. D., & B. W. Hoeksema. 1998. Distichopora vervoorti, 

a new shallow-water stylasterid coral (Cnidaria: 

Hydrozoa: Stylasteridae) from Bali, Indonesia. Zoologische 

Verhandelingen 323: 311–318. 

Calder, D. R. 1988. Shallow-water hydroids of Bermuda. 

The Athecatae. – Royal Ontario Museum Life Sciences 

Contributions 148: 1–107. 

Calder, D. R. 1991. Shallow-water hydroids of Bermuda: the 

Thecatae, exclusive of Plumularioidea. – Royal Ontario 

Museum Life Sciences Contributions 154: 1–140. 

Calder, D. R. 1997. Shallow-Water Hydroids of Bermuda: 

(Superfamily Plumularoidea). – Royal Ontario Museum 

Life Science Contributions 161: 1–85. 

Campenhausen, B. von. 1896a. Hydroiden von Ternate, 

nach den Sammlungen Prof. W. Kükenthal’s. – 

Zoologischer Anzeiger 19: 103–107. 

Campenhausen, B. von. 1896b. Hydroiden von Ternate. – 

Abhandlungen herausgegeben von der Senckenbergischen 

Naturforschenden Gesellschaft 23: 297–320. 

Clarke, S. F. 1875. Descriptions of new and rare species of 

hydroids from the New England coast. – Transactions of 

the Connecticut Academy of Sciences 3: 58–66. 

Clarke, S. F. 1876. Report on the hydroids collected on the 

coast of Alaska and the Aleutian Islands by W.H. Dall, 

U.S. Coast Survey, and party, from 1871 to 1874 inclusive. 

– Proceedings of the Academy of Natural Sciences 

of Philadelphia 1876: 209–235, plates. 

Clarke, S. F. 1879. Report on the Hydroida collected during 

the Exploration of the Gulf Stream of Mexico by Alexander 

Agassiz, 1877–78. – Bulletin of the Museum of 

Comparative Zoology 5: 239–252, pl. 5.


Clarke, S. F. 1907. Reports on the scientific results of the 

expedition to the eastern tropical Pacific, in charge of 

Alexander Agassiz, by the U. S. Fish Commission 

steamer ‘Albatros’, from October 1904 to March 1905, 

Lieut.-Commander L. M. Garrett, U. S. N., commanding. 

VIII The hydroids. – Memoirs of the Museum of comparative 

Zoology at Harvard College 35: 1–18. 

Cooke, W. J. 1975. Shallow water hydroids from Enewetak 

Atoll, Marshall Islands. – Micronesica 11: 85–108, pls 

1–6. 

Cornelius, P. F. S. 1979. A revision of the species of 

Sertulariidae (Coelenterata: Hydroida) recorded from 

Britain and nearby seas. – Bulletin of the British Museum 

34: 243-321. 

Cornelius, P. F. S. 1975a. The hydroid species of Obelia 

(Coelenterata, Hydrozoa: Campanulariidae), with notes 

on the medusa stage. – Bulletin of the British Museum, 

Zoology 28: 251–293. 

Cornelius, P. F. S. 1975b. A revision of the species of 

Lafoeidae and Haleciidae (Coelenterata: Hydroida) recorded 

from Britain and nearby seas. – Bulletin of the 

British Museum, Zoology 28: 373-426. 

Cornelius, P. F. S. 1982. Hydroids and medusae of the family 

Campanulariidae recorded from the eastern north Atlantic, 

with a world synopsis of genera. – Bulletin of the 

British Museum, Zoology 42: 37–148. 

Cornelius, P. F. S. 1995a. North-west European thecate 

hydroids and their medusae. Part 1. Introduction, Laodiceidae 

to Haleciidae. – Synopses of the British Fauna 

(New Series) 50: 1–347. 

Cornelius, P. F. S. 1995b. North-west European thecate 

hydroids and their medusae. Part 2. Sertulariidae to 

Campanulariidae. – Synopses of the British Fauna (New 

Series) 50: 1–386. 

Cornelius, P. F. S., & C. Östman. 1986. On the names of two 

species of the genus Clytia Lamouroux, 1812 (Cnidaria, 

Hydrozoa) common in western Europe. – Bulletin of 

Zoological Nomenclature 43: 163–169. 

Ehrenberg, C. G. 1834. Beiträge zur physiologischen Kenntnis 

der Corallenthiere im allgemeinen, und besonders des 

rothen Meeres, nebst einem Versuche zur physiologischen 

Systematik derselben. – Abhandlungen der Königlichen 

Akademie der Wissenschaften, Berlin 1: 225– 

380. 

Ellis, J., & D. Solander. 1786. The Natural History of Many 

Curious and Uncommon Zoophytes, Collected from Various 

Parts of the Globe by the late John Ellis, Esq. F.R.S. 

Soc. Reg. Upsal. Soc. Author of the Natural History 

of English Corallines, and other Works. Systematically 

Arranged and Described by the Late Daniel Solander, 

M.D. F.R.S. & c. with sixty-two plates engraven by 

principal artists. – Benjamin White and Peter Elmsly, 

London, 206 pp., 63 pls. 

Esper, E. J. C. 1793. Die Pflanzentiere in Abbildungen nach 

der Natur mit Farben erleuchtet. Vol. 2. – Bauer & 

Raspe, Nürnberg, 304 pp. 

Fleming, J. 1820. Observations on the natural history of 

Sertularia gelatinosa of Pallas. – Edinburgh Philosophical 

Journal 2: 82–89. 

Fraser, C. M. 1912. Some hydroids of Beaufort, North 

249 

Carolina. – Bulletin of the Unites States Bureau of Fisheries 

30: 337–387. 

Fraser, C. M. 1937. Hydroids of the Pacific coast of Canada 

and the United States. The University of Toronto Press, 

Toronto, 208 pp., 44 pls. 

Fraser, C. M. 1938. Hydroids of the 1934 Allan Hancock 

Pacific Expedition. – Allan Hancock Pacific Expeditions 

4: 1–105. 

Fraser, C. M. 1944. Hydroids of the Atlantic coast of North 

America. – The University of Toronto Press, Toronto, pp. 

1–451, pls 1–94. 

Fraser, C. M. 1948. Hydroids of the Allan Hancock Pacific 

Expeditions since March, 1938. Allan Hancock Pacific 

Expeditions 4: 179–343. 

Garcia Corrales, P., A. Aguirre Inchaurbe, & D. Gonzalez 

Mora. 1980. Contribución al conocimiento de los hidrozoos 

de las costas españolas. Parte 3: Sertulariidae. – 

Boletin del Instituto Español de Oceanografia 6: 3–67. 

Garcia Corrales, P., & A. Aguirre. 1985. La especie Halocordyle 

disticha (Goldfuss, 1820), y sus sinonimias. – 

Boletin del Instituto Español de Oceanografia 2: 85–96. 

Gemerden-Hoogeveen, G. C. H. van. 1965. Hydroids of the 

Caribbean : Sertulariidae, Plumulariidae and Aglaopheniidae. 

– Studies on the fauna of Curaçao and other 

Caribbean Islands 22: 1–87. 

Genzano, G. N. 1992. La Fauna de hydropolypos (Cnidaria) 

del litoral de Buenos Aires, Argentina. I. – Neotropica 

38: 141–148. 

Gibbons, M. J., & J. S. Ryland. 1989. Intertidal and shallow 

water hydroids from Fiji. 1. Athecata to Sertulariidae. – 

Memoirs of the Queensland Museum 27: 377–432. 

Gili, J. M., W. Vervoort, & F. Pages. 1989. Hydroids from 

the west African coast: Guinea Bissau, Namibia and 

South Africa. – Scientia Marina 53: 67–112. 

Gmelin, J. F. 1791. C. Linnaeus, Systemae Naturae. Thirteenth 

edition, edited by. J. F. Gmelin. Vol. 1, part 6 

(vermes), pp. 3021–3910. 

Goldfuss, G. A. 1820. Handbuch der Zoologie. Erste Abteilung. 

– Schrag, Nürnberg, 606 pp. 

Gravier-Bonnet, N. 1979. Hydraires semi-profonds de 

Madegascar, (Coelenterata Hydrozoa), étude systématique 

et écologique. – Zoologische Verhandelingen, 

Leiden 169: 1–76. 

Gravier-Bonnet, N., & A. E. Migotto. 2000. Gonangium 

development and medusoid of Nemalecium lighti (Hargitt, 

1924) (Cnidaria : Hydrozoa, Haleciidae). – Scientia 

Marina 64: 207–213. 

Gray, J. E. 1843. Additional radiated animals and annelides. 

pp. 292. – In: E. Dieffenbach, Travels in New Zealand: 

with contributions to the geography, geology, botany, 

and natural history of that country. Vol. 2, London. 

Hadzi, J. 1914. Poredbena hidroidska istraivanja. III. Haleciella 

microtheca g. n., sp.n.; Georginella diaphana g. 

n., sp. n.; Halanthus adriaticus g. n., sp. n.; Campanopsis 

clausa (Hadzi) i o porodici Campanopsida uopæe. – Rad 

Jugoslavenske Akademije Zanosti i Umjetnosti 202: 

191–241. (German translation in: Bulletin des Traveaux 

de la Classe des Sciences mathématigues et naturelles 2: 

50–59) 

Haeckel, E. 1879. Das System der Medusen. Erster Teil einer 

Monographie der Medusen. – Denkschriften der Medi-

250 

cinisch-Naturwissenschaftlichen Gesellschaft zu Jena 1: 

1–360, 20 pls. 

Hargitt, C. W. 1924. Hydroids of the Philippine Islands. – 

Philippine Journal of Science 24: 467–507, pls 1–6. 

Hickson, S. J., & H. M. England. 1905. The Stylasterina of 

the Siboga Expedition. – Siboga Expeditie 8: 1–26, 3 pls. 

Hirohito, Emperor of Japan. 1969. Some hydroids from the 

Amakusa Islands. – Biological Laboratory of the Imperial 

Household, Tokyo, 32 pp. 

Hirohito, Emperor of Japan. 1977. Five hydroid species from 

the Gulf of Aqaba, Red Sea. – Biological Laboratory of 

the Imperial Household, Tokyo, 26 pp. 

Hirohito, Emperor of Japan. 1983. Hydroids from Izu Oshima 

and Nijima. – Biological Laboratory of the Imperial 

Household, Tokyo, 83 pp. 

Hirohito, Emperor of Japan. 1988. The hydroids of Sagami 

Bay collected by His Majesty the Emperor of Japan. 

– Biological Laboratory of the Imperial Household, 

Tokyo, pp.1–179, 4 pls. 

Hirohito, Emperor of Japan 1995. Hydroids of Sagami Bay. 

II. Thecata. – Biological Laboratory of the Imperial 

Household, Tokyo, 355 pp., 13 pls. 

Inaba, M. 1892. The hydroids collected at Misaki, Miura, 

Soshu (in Japanese). – Zoological Magazine 4: 93–101, 

124–131. 

Jäderholm, E. 1896. Ueber aussereuropäische Hydroiden 

des zoologischen Museums der Universität Upsala. – 

Bihang till Kungliga Svenska Vetenskaps-akademiens 

Handlingar 4: 1–20, pls 1–2. 

Jäderholm, E. 1903. Aussereuropäische Hydroiden im 

schwedischen Reichsmuseum. – Arkiv för Zoologi 1: 

259–312, pls 12–15. 

Jäderholm, E. 1919. Zur Kenntis der Hydroidenfauna Japans. 

– Arkiv för Zoologi 12: 1–34, pls 1–6. 

Jäderholm, E. 1920. On some exotic hydroids in the Swedish 

Zoological State Museum. – Arkiv för Zoologi 13: 1–11, 

pls 1–2. 

Jarvis, F. E. 1922. The hydroids from the Chagos, Seychelles 

and other islands and from the coasts of British East 

Africa and Zanzibar. – Transaction of the Linnean Society 

of London, Zoology 18: 331–360, pls 24–26. 

Kirchenpauer, G. H. 1872. Ueber die Hydroidenfamilie Plumulariidae, 

einzelne Gruppen derselben und ihre Fruchtbehälter. 

I. Aglaophenia. – Abhandlungen aus dem Gebiet 

der Naturwissenschaften, herausgegeben von dem 

naturwissenschaftlichen Verein in Hamburg 5: 1–52, 

plates 1–8. 

Kirchenpauer, G. H. 1876. Ueber die Hydroidenfamilie Plumulariidae, 

einzelne Gruppen derselben und ihre Fruchtbehälter. 

II. Plumularia und Nemertesia. – Abhandlungen 

aus dem Gebiet der Naturwissenschaften, herausgegeben 

von dem naturwissenschaftlichen Verein in Hamburg 

6: 1–59, plates 1–8. 

Kirkpatrick, R. 1890. Reports on the collections made in 

Torres Straits by Professor A. C. Haddon, 1888-1889. 

Hydroida and Polyzoa. – Proceedings of the Royal Dublin 

Society, n. s. 6: 603–626. 

Kramp, P. L. 1941. Notes on the hydroid Campanulina 

paniculata G.O. Sars. – Göteborgs Kunglige Vetenskaps- 

och Vitterhets-Samhälles Handlingar, Ser. B 1: 1– 

11. 

P. SCHUCHERT 

Kramp, P. L. 1961. Synopsis of the medusae of the world.– 

Journal of the Marine Biological Association of the U. K. 

40, 1–469. 

Kramp, P. L. 1965. The Hydromedusae of the Pacific and 

Indian Oceans. – Dana Report 63: 1–162. 

Kramp, P. L. 1968. The Hydromedusae of the Pacific and 

Indian Oceans. Sections II and III. – Dana Report 72: 1– 

200. 

Lamarck, J. B. P. A. de. 1816. Histoire naturelle des Animaux 

sans Vertébres, vol. 2. Paris, Verdière, 568 pp. 

Lamouroux, J. V. F. 1816. Histoire des Polypiers coralligènes 

flexibles, vulgairemant nommés Zoophytes. F. 

Poisson, Caen, 559 pp. 

Lamouroux, J. V. F. 1824. Description des polypiers flexibles, 

pp. 603–643, pls 88–95. – In: L. de Freycinet. Voyage 

autour du monde, entrepris par ordre du Roi, éxecuté 

sur les corvettes l’Uranie et la Physicienne, pendant les 

années 1817, 1818, 1819 et 1820. Zoologie, rédigé par 

MM. J. R. C. Quoy et J. P. Gaimard, Pillet Aîné, Paris. 

Leloup, E. 1930a. Sur un hydropolype nouveau, Thecocarpus 

leopoldi nov. sp., des Indes orientales néerlandaises. 

– Bulletin du Musée Royal d’Histoire Naturelle 

de Belgique 6: 1–3. 

Leloup, E. 1930b. Coelentérés hydropolypes. In: Résultats 

Scientifiques du Voyage aux Indes Orientles Néerlandaises 

de LL. AA. RR. le Prince et la Princesse Léopold 

de Belgique. – Mémoires du Musée Royal d’Histoire 

Naturelle de Belgique, hors série 2: 1–18, pl. 1. 

Leloup, E. 1932. Répartition géographique de l’Aglaophenia 

cupressina Lamouroux. – Bulletin du Musée Royal 

d’Histoire Naturelle de Belgique 8: 1–3. 

Leloup, E. 1937. Hydropolypes et Scyphopolypes recueillis 

par C. Dawydoff sur les côtes de l’Indochine française. – 

Bulletin du Musée Royal d’Histoire Naturelle de Belgique 

12: 1–73. 

Leloup, E. 1938. Quelques hydropolypes de la baie de 

Sagami, Japon. – Bulletin du Musée Royal d’Histoire 

Naturelle de Belgique 14: 1–22. 

Leloup, E. 1960. Hydropolypes du Muséum National d’Histoire 

naturelle de Paris. – Mémoirs du Muséum national 

d’Histoire naturelle de Paris, n. ser. 17: 217–241. 

Leloup, E. 1974. Hydropolypes calyptoblastiques du Chili. 

Report no. 48 of the Lund University Chile Expedition 

1948-1949. – Sarsia 55: 1–62. 

Lendenfeld, R. v. 1885a. The Australian Hydromedusae. – 

Proceedings of the Linnean Society of New South Wales 

9: 206–241, 345–353, 401–420, 467–492, 581–634, pls 

6–8, 12–17, 20–29. 

Linneaus, C. 1758. Systema naturae per regna tria naturae, 

secundum classes, ordines, genera, species cum characteribus, 

differentiis, synonymis, locis. Edition decima, 

reformata. Laurentii Salvii, Holmiae, 823 pp. 

Linneaus C. 1767. Systema naturae per regna tria naturae, 

secundum classes, ordines, genera, species cum characteribus, 

differentiis, synonymis, locis. Tomus I. Pars II. 

Editio duodecima, reformata. Laurentii Salvii, Holmiae, 

pp. 533–1317. 

Mammen, T. A. 1963. On a collection of hydroids from 

South India. I. Suborder Athecata. – Journal of the Marine 

biological Association of India 5: 27–61. 

Mammen, T. A. 1965. On a collection of hydroids from


South India. II. Suborder Thecata (excluding family 

Plumulariidae). – Journal of the Marine biological Association 

of India 7: 1–57. 

Mammen, T. A. 1967. On a collection of hydroids from 

South India. III. Family Plumulariidae. – Journal of the 

Marine biological Association of India 7: 291–324. 

Marktanner-Turneretscher, G. 1890. Hydroiden des K. & K. 

Naturhistorischen Hofmuseums. – Annalen des K. K. 

Naturhistorischen Hofmuseums 5: 195–286. 

Marques, A. C., H. Mergner, R. Höinghaus, C. M. D. Santos 

& W. Vervoort. 2000. Morphological study and taxonomical 

notes on Eudendriidae (Cnidaria: Hydrozoa: 

Athecate/Anthomedusae). – Zoologische Mededelingen, 

Leiden 74: 75–118. 

McCrady, J. 1859a. Description of Oceania (Turritopsis) 

nutricula nov. spec. and the embryological history of a 

singular medusan larva, found in the cavity of its bell. – 

Proceedings of the Elliot Society of Natural History 1: 

55–90, pls 4–7. 

Medel, M. D. & W. Vervoort. 1998. Atlantic Thyroscyphidae 

and Sertulariidae (Hydrozoa, Cnidaria) collected 

during the CANCAP and Mauritania-II expeditions of 

the National Museum of Natural History, Leiden, the 

Netherlands. – Zoologische Verhandelingen, Leiden 

320: 1–85. 

Medel, M. D. & W. Vervoort. 2000. Atlantic Haleciidae and 

Campanulariidae (Hydrozoa, Cnidaria) collected during 

the CANCAP and Mauretania-II expeditions of the 

National Museum of Natural History, Leiden, the 

Netherlands. – Zoologische Verhandelingen, Leiden 

330: 1–68. 

Meneghini, G. 1845. Osservazioni sull’ ordine delle 

sertulariee della classe dei polipi. – Memorie dell’ 

Imperiale Reale Instituto Veneto di Scienze, Lettere ed 

Arti 2: 183–199. 

Migotto, A. E. 1996. Benthic shallow-water hydroids 

(Cnidaria, Hydrozoa) of the coast of São Sebastião, 

Brazil, including a checklist of Brazilian hydroids. – 

Zoologische Verhandelingen, Leiden 306: 1–125. 

Migotto, A. E., & L. P. de Andrade. 2000. The life cycle of 

Hebella furax (Cnidaria: Hydrozoa): a link between a 

lafoeid hydroid and a laodiceid medusa. – Journal of 

Natural History 34: 1871–1888. 

Millard, N. A. H. 1958. Hydrozoa from the coasts of Natal 

and Portuguese East Africa. Part I. Calyptoblastea. – 

Annals of the South African Museum 44: 165–226. 

Millard, N. A. H. 1964. The Hydrozoa of the south and west 

coasts of South Africa. Part II. The Lafoeidae, 

Syntheciidae and Sertulariidae. – Annals of the South 

African Museum 48: 1–56. 

Millard, N. A. H. 1968. South African hydroids from Dr. Th. 

Mortensen’s Java-South Africa expedition 1930. – 

Videnskabelige Meddelelser fra Dansk Naturhistorisk 

Forening i København 131: 251–288. 

Millard, N. A. H. 1975. Monograph on the Hydroida of 

southern Africa. – Annals of the South African Museum 

68: 1–513. 

Millard, N. A. H. 1980. The South African Museum’s 

Meiring Naude cruises. Part 11. Hydroida. – Annals of 

the South African Museum 82: 129–153. 

Millard, N. A. H., & J. Bouillon. 1973. Hydroids from the 

251 

Seychelles (Coelenterata). – Annales du Musée Royal de 

l’Afrique Centrale, série In-8°, Sciences Zoologiques 

206: 1–106, pls 1–5. 

Millard, N. A. H., & J. Bouillon. 1975. Additional hydroids 

from the Seychelles. – Annals of the South African 

Museum 69: 1–15. 

Morri, C. 1982. Sur la presence en Mediterranée de Garveia 

franciscana (Torrey 1902) (Cnidaria, Hydroida). – 

Cahiers de Biologie Marine 23: 381–391. 

Mortensen, T. 1923. The Danish Expedition to the Kei 

Islands 1922. – Videnskabelige Meddelelser fra Dansk 

Naturhistorisk Forening 76: 25-99, pls 1–3. 

Motz-Kossowska, S. 1911. Contribution à la connaissance 

des hydraires de la Méditerranée occidentale. II.- 

Hydraires calyptoblastiques. – Archives de Zoologie 

Expérimentale et Générale 6: 325–352. 

Mulder, J. F. & R. E. Trebilcock. 1909. Notes on Victorian 

Hydroida, with descriptions of new species. – The 

Geelong Naturalist 4: 29–35, pl. 1. 

Mulder, J. F., & R. E. Trebilcock. 1911. Notes on Victorian 

Hydroida, with description of new species. (Continued). 

– The Geelong Naturalist 4: 115–124. 

Norman A. M. 1867. Report of the committee appointed for 

the purpose of explorating the coasts of the Hebrides by 

means of the dredge. Part II. On the Crustacea, 

Echinodermata, Polyzoa, Actinozoa, and Hydrozoa. – 

Report of the British Association for the Advancement of 

Science 1866: 193–206. 

Nutting, C. C. 1900. American Hydroids. Part I. The 

Plumularidae. – Smithsonian Institution, United States 

National Museum Special Bulletin 4: 1–285. 

Nutting, C. C. 1904. American Hydroids. Part II. The 

Sertularidae. – Smithsonian Institution, United States 

National Museum Special Bulletin 4: 1–325, pls 1–41. 

Nutting, C. C. 1905. Hydroids of the Hawaiian Islands 

collected by the steamer Albatross in 1902. – Bulletin of 

the United States Fish Commission for 1903 23: 931– 

959, pls 1–13. 

Nutting, C. 1927. Report on Hydroida collected by the 

Unites States Fisheries steamer Albatross in the 

Philippine region 1910. – Bulletin of the United States 

National Museum 100: 195-242. 

Östman, C., S. Piraino & W. Kem. 1991. Nematocysts of the 

Mediterranean hydroid Halocordyle disticha. – Hydrobiologia 

216–217: 607–613. 

Pages, F., J.-M. Gili & J. Bouillon. 1992. Medusae 

(Hydrozoa, Scyphozoa, Cubozoa) of the Benguela 

Current (southeastern Atlantic). – Scientia Marina 56: 1– 

64. 

Peña Cantero, A. L. & A. M. Garcìa Carrascosa. 2002. The 

benthic hydroid fauna of the Chafarina Islands (Alborán 

Sea, western Mediterranean). – Zoologische Verhandelingen, 

Leiden 337: 1–180. 

Pennycuik, P. R. 1959. Faunistic record from Queensland. 

Part V. Marine and Brackish Water Hydroids. – Papers of 

the Department of Zoology of the University of 

Queensland 1: 141–210. 

Petersen, K. W. 1990. Evolution and taxonomy in capitate 

hydroids and medusae (Cnidaria: Hydrozoa). – 

Zoological Journal of the Linnean Society 100: 101–231. 

Philbert, M. 1936. Études sur Cladocoryne floccosa Rotch. –

252 

Bulletin de l’ Institut océanographique de Monaco 708: 

1–16. 

Pictet, C. 1893. Etude sur les hydraires de la Baie d’Amboine. 

– Revue Suisse de zoologie 1: 1–64. 

Ralph, P. M. 1958. New Zealand thecate hydroids. Part II. - 

Families Lafoeidae, Lineolariidae, Haleciidae and Syntheciidae. 

– Transactions of the Royal Society of New 

Zealand 85: 301–356. 

Ralph, P. M. 1961a. New Zealand thecate hydroids. Part III. 

- Family Sertulariidae. – Transactions of the Royal Society 

of New Zealand 88: 749–838. 

Ralph, P. M. 1961b. New Zealand thecate hydroids. Part IV. 

- The family Plumulariidae. – Transactions of the Royal 

Society of New Zealand, Zoology 1: 19–74. 

Ramil, F. & W. Vervoort. 1992. Report on the Hydroida 

collected by the ‘BALGIM’ expedition in and around the 

Strait of Gibraltar. Zoologische Verhandelingen, Leiden 

277: 1–262. 

Rees, W. J. & W. Vervoort. 1987. Hydroids from the John 

Murray Expedition to the Indian Ocean, with revisory 

notes on Hydrodendron, Abietinella, Cryptolaria and 

Zygophylax (Cnidaria: Hydrozoa). – Zoologische Verhandelingen, 

Leiden 237: 1–209. 

Rho, B. J. 1967. Marine hydroids from the west and south sea 

of Korea. – Korean Culture Research Institute 10: 341– 

360. 

Rho, B. J. 1969. Studies on the marine hydroids in Korea. – 

Journal of the Korean Research Institute for better Living, 

Ewha Womans University 2: 161–172, pls 1–2. 

Ritchie, J. 1907. On Collections of the Cape Verde Island 

Marine Fauna, made by Cyril Crossland, M. A. (Cantab.), 

B.Sc. (Lond.), F.Z.S., of St. Andrews University, 

July to September, 1904. – Proceedings of the Zoological 

Society of London 1907: 488–514. 

Ritchie, J. 1909b. New Species and Varieties of Hydroids 

Thecata from the Andaman Islands. – Annals and Magazine 

of Natural History (8) 3: 524–528. 

Ritchie, J. 1910a. Hydroids of the Indian Museum. No. 1. – 

Records of the Indian Museum 5: 1–30, pl. 4. 

Ritchie, J. 1910b. The marine fauna of the Mergui Archipelago, 

lower Burma etc. - the Hydroids. – Proceedings 

of the Zoological Society of London 1910: 799–825, pls. 

Ritchie, J. 1910c. Hydroids from Christmas Island, Indian 

Ocean. – Proceedings of the Zoological Society of London 

1910: 826–836. 

Russell, F. S. 1953. The Medusae of the British Isles. Anthomedusae, 

Leptomedusae, Limnomedusae, Trachymedusae 

and Narcomedusae. – Cambridge University Press, 

London, 530 pp., 35 pls. 

Ryland, J. S. & M. J. Gibbons. 1991. Intertidal and shallow 

water hydroids from Fiji. 2. Plumulariidae and Aglaopheniidae. 

– Memoirs of the Queensland Museum 30: 

525–560. 

Sars, G. O. 1874. Bidrag til Kundskaben om Norges Hydroider. 

– Forhandelinger i Videnskabs-Selskabet i Kristiana 

1873: 91–150, pls 2–5. 

Sars, M. 1850. Beretning om en i sommeren 1849 foretagen 

zoologisk reise i Lofoten og Finmarken. – Nyt Magazin 

for Naturvidenskaberne 9: 110–164. 

Schuchert, P. 1996. The marine fauna of New Zealand: 

P. SCHUCHERT 

athecate hydroids and their medusae. – New Zealand 

Oceanographic Institute Memoir 106: 1–160. 

Schuchert, P. 1997. Review of the family Halopterididae 

(Hydrozoa, Cnidaria). – Zoologische Verhandelingen, 

Leiden 309: 1–162. 

Schuchert, P. 2001. The hydroids (Cnidaria, Hydrozoa) of 

Greenland and Iceland. Meddelelser om Grønland, Bioscience 

53: 1–184. 

Splettstösser, W. 1929. Beiträge zur Kenntnis der Sertulariiden. 

Thyroscyphus Allm., Cnidoscyphus nov. gen., 

Parascyphus Ritchie. – Zoologische Jahrbücher, Abteilung 

für Systematik, Oekologie und Geographie der 

Tiere 58: 1–134. 

Spoel, S. van der & J. Bleeker. 1988. Medusae from the 

Banda Sea and Aru Sea plankton, collected during the 

Snellius II Expeditions, 1984-1985. – Indo-Malayan 

Zoology 5: 161–202. 

Stechow, E. 1909. Hydroidpolypen der japanischen Ostküste. 

I. Teil: Athecata und Plumularidae. In: F. Doflein, 

Beiträge zur Naturgeschichte Ostasiens. – Abhandlungen 

der Mathematisch-Physikalische Klasse der Königlichen 

Bayerischen Akademie der Wissenschaften, 

Supplement Band 1: 1–111, pls 1–7. 

Stechow, E. 1913. Hydroidpolypen der japanischen Ostküste. 

II. Teil: Campanularidae, Halecidae, Lafoeidae, 

Campanulinidae und Sertularidae, nebst Ergänzungen 

zu den Athecata und Plumularidae. – In: F. Doflein, 

Beiträge zur Naturgeschichte Ostasiens. – Abhandlungen 

der Mathematisch-Physkalische Klasse der Königlichen 

Bayerischen Akademie der Wissenschaften, 

Supplement Band 3: 1–162. 

Stechow, E. 1919. Zur Kenntnis der Hydroidenfauna des 

Mittelmeeres, Amerikas und anderer Gebiete, nebst Angaben 

über einige Kirchenpauer’sche Typen von Plumulariden. 

– Zoologische Jahrbücher, Abteilung Systematik, 

Oekologie und Geographie der Tiere 42: 1–172. 

Stechow, E. 1921. Ueber Hydroiden der Deutschen Tiefsee- 

Expedition, nebst Bemerkungen über einige andre 

Formen. – Zoologischer Anzeiger 53: 223–236. 

Stechow, E. 1922. Zur Systematik der Hydrozoen, Stromatoporen, 

Siphonophoren, Anthozoen und Ctenophoren. 

– Archiv für Naturgescheschichte 88: 141–155. 

Stechow, E. 1923. Neue Hydroiden der Deutschen Tiefsee- 

Expedition, nebst Bemerkungen über einige andre Formen. 

– Zoologischer Anzeiger 56: 1–20. 

Stechow, E. 1925. Hydroiden von West- und Südwestaustralien 

nach den Sammlungen von Prof. Dr. Michaelsen 

und Prof. Dr. Hartmeyer. – Zoologische Jahrbücher, 

Abteilung Systematik, Oekologie und Geographie der 

Tiere 50: 191–270. 

Stechow, E. 1932. Neue Hydroiden aus dem Mittelmeer und 

dem Pazifischen Ozean, nebst Bemerkungen über einige 

wenig bekannte Formen. – Zoologischer Anzeiger 100: 

81–92. 

Stechow, E. & H. C. Müller. 1923. Hydroiden von den Aru- 

Inseln. – Abhandlungen der Senckenbergischen naturforschenden 

Gesellschaft 35: 459–478. 

Studer, T. 1878. Uebersicht der Steinkorallen aus der Familie 

der Madreporina aporosa, Eupsammina, und Turbinaria, 

welche auf der Reise S.M.S. Gazelle um die Erde 

gesammelt wurden. – Monatsberichte der Königlich


Preussschen Akademie der Wissenschaften zu Berlin 

1877: 625–654, 4 pls. 

Svoboda, A. & P. F. S. Cornelius 1991. The European and 

Mediterranean species of Aglaophenia (Cnidaria: 

Hydrozoa). – Zoologische Verhandelingen, Leiden 274: 

1–72. 

Thompson, D. A. W. 1887. The Hydroida of the Vega Expedition. 

– Vega Expeditionens Vetenskapliga Iakttagelser 

4: 387–400. 

Thornely, L. R. 1900. The Hydroid Zoophytes collected by 

Dr Willey in Southern Seas. – In: Zoological results 

based on material from New Britain, New Guinea, 

Loyality Islands and elsewhere collected during the years 

1895-97 by A. Willey. Cambridge, pp. 451–458, pl. 44. 

Thornely, L. A. 1904. Report on the Hydroida collected by 

professor Herdman, at Ceylon, in 1902. – Report to the 

Government of Ceylon on the pearl oyster fisheries of the 

Gulf of Manaar 2, suppl. Rep. no. 8: 107–126. 

Torrey, H. B. 1902. The Hydroida of the Pacific Coast of 

North America. – University of California Publications 

Zoology 1: 1–104, pls 1–11. 

Totton, A. K. 1930. Coelenterata. Part V.- Hydroida. – 

British Antarctic (“Terra Nova”) Expedition, 1910, 

Natural History Report, Zoology 5: 131–252, pls 1–3. 

Vannucci-Mendes, M. 1946. Hydroida Thecaphora do 

Brasil. – Arquivos de Zoologia do Estado de São Paulo 4: 

535–597, pls 1–7. 

Vannucci, M. 1949. Hydrozoa do Brasil. – Boletim da 

Faculdade de Filosofia, Ciências da Universidade de São 

Paulo, Zoologia 14: 219–266. 

Versluys, J. J. 1899. Hydraires calyptoblastes recueillis dans 

la mer des Antilles, pendant l’une des croisières 

accomplies par le comte R. de Dalmas sur son yacht 

“CHAZALIE”. – Mémoires de la Societé Zoologique de 

France 12: 29–58. 

Vervoort, W. 1941. The Hydroida of the Snellius Expedition 

(Milleporidae and Stylasteridae excluded). Biological 

results of the Snellius Expedition XI. – Temminckia 6: 

186–240. 

Vervoort, W. 1959. The Hydroida of the tropical west coast 

of Africa. – Atlantide Report 5: 211–325. 

Vervoort, W. 1964. Note on the distribution of Garveia 

franciscana (Torrey) and Cordylophora caspia (Pallas, 

1771) in the Netherlands. – Zoologische Mededelingen, 

Leiden 39: 125–146. 

Vervoort, W. 1966. Bathyal and abyssal hydroids. – 

Galathea Report 8: 97–173. 

Vervoort, W. 1967. The Hydroida and Chondrophora of the 

Israel South Red Sea Expedition In: Israel South Red Sea 

Expedition Reports, No. 25. – Bulletin of the Sea 

Fisheries Research Station of Israel 43: 18–54. 

Vervoort, W. 1968. Report on a collection of Hydroida from 

the Caribbean region, including an annotated checklist of 

Caribbean hydroids. – Zoologische Verhandelingen, 

Leiden 92: 1–124. 

Vervoort, W. 1993. Cnidaria, Hydrozoa, Hydroida: 

Hydroids from the Western Pacific (Philippines, 

Indonesia and New Caledonia. 1: Sertulariidae (Part 1). – 

Mémoires du Muséum national d’Histoire Naturelle de 

Paris 158: 89–298. 

Vervoort, W., & P. Vasseur. 1977. Hydroids from French 

253 

Polynesia with notes on distribution and ecology. – 

Zoologische Verhandelingen, Leiden 159: 3–98. 

Warren, E. 1908. On a collection of hydroids, mostly from 

the Natal coast. – Annales of the Natal Museum 1: 269– 

355. 

Watson, J. E. 1973. Hydroids. In: Pearson Island Expedition 

9. – Transactions of the Royal Society of South Australia 

97: 153–200. 

Watson, J. E. 1985. The genus Eudendrium (Hydrozoa: 

Hydroida) from Australia. – Proceedings of the Royal 

Society of Victoria 97: 179–221. 

Watson, J. E. 1993. Two new species of Haleciidae 

(Hydrozoa: Hydroida) from southern Australia. – 

Proceedings of the Royal Society of Victoria 105: 81–84. 

Watson, J. E. 1994. New records and redescriptions of 

thecate hydroids from southern Australia. – Proceedings 

of the Royal Society of Victoria 106: 147–162. 

Watson, J. E. 1997. The hydroid fauna of the Houtman 

Abrolhos Islands, Western Australia. – Pp. 503–546 in F. 

E. Wells (ed): Proceedings of the Seventh International 

Marine Biological Workshop: The Marine Flora and 

Fauna of the Houtman Abrolhos Islands, Western 

Australia. Western Australian Museum, Perth. 

Watson, J. E. 1999. Hydroids (Hydrozoa: Anthoathecata) 

from the Beagle Gulf and Darwin Harbour, Northern 

Australia. – The Beagle, Records of the Museums and 

Art Galleries of the Northern Territory 15: 1–21. 

Watson, J. E. 2000. Hydroids (Hydrozoa: Leptothecatae) 

from the Beagle Gulf and Darwin Harbour, northern 

Australia. – The Beagle, Records of the Museums and 

Art Galleries of the Northern Territory 16: 1–82. 

Weisman, A. 1883. Die Entstehung der Sexualzelllen bei 

den Hydromedusen. Zugleich ein Beitrag zur Kenntnis 

des Baues und der Lebensgeschichte dieser Gruppe. 

Gustav Fischer, Jena, 295 pp. 

Weltner, W. 1900. Hydroiden von Amboina und Thursday 

Islands. – Denkschriften der medizinisch naturwissenschaftlichen 

Gesellschaft von Jena 8: 583–590, pl. 46. 

Werner, B. 1968. Polypengeneration und Entwicklungsgeschichte 

von Eucheilota maculata (Thecata-Leptomedusae). 

– Helgoländer wissenschaftliche Meeresuntersuchungen 

18: 136–168. 

Wheeler, Q. D. & R. Meier. 2000. Species Concepts and 

Phylogenetic Theory: A Debate. Columbia University 

Press, New York. 230 pp. 

Whitelegge, T. 1899. The Hydrozoa, Scyphozoa, Actinozoa, 

and Vermes of Funafuti. – In: The atoll of Funafuti, Elliot 

Group; its zoology, botany, ethnology, and general 

structure based on collections made by Mr. Charles 

Hedley of the Australian Museum, Sydney, N.S.W. – 

Memoirs of the Australian Museum 3: 371–394, pls 23– 

27. 

Wright, T. S. 1859. Observations on British zoophytes. – 

Edinburgh New Philosophical Journal 10: 105–114, pls 

8–9. 

Submitted 5.ii.2002; accepted 5.xi.2002

254 

P. SCHUCHERT 

Appendix 1 

Station data of the Kei Island Expedition, after Mortensen (1923); only those stations which yielded identifiable hydroids are 

included. Data given as follows: station number; locality; decimal coordinates (if available); depth; collection date; bottom 

type. Mortensen (1923) provides more details and also maps. 

1. Kei Islands; 5.57°S, 132.83°E; 370 m; 30 Mar 1922; mud 

3. Kei Islands; 5.53°S, 132.6°E; 245 m; 31 Mar 1922; sand 

4. Kei Islands; 5.53°S, 132.63°E; 250 m; 3 May 1922; sand 

7. Kei Islands; 5.64°S, 132.43°E; 196 m; 5 Apr 1922; sandy 

mud, small stones 

11. Kei Islands, off Tual; 20 m; 9 Apr 1922; sand, shells, 

corals 

12. Kei Islands; 5.5°S, 132.58°E; 320 m; 9 Apr 1922; sand, 

shells, coral 

14. Kei Islands, south of Doe Roa; 40 m; 10 Apr 1922; sand 

15. Kei Islands, South of Doe Roa; 5 m; 10 Apr 1922; sand 


Lithothamnion 

18. Kei Islands, Doe Roa Strait; 40 m; 12 Apr 1922; sand, 

corals 

19. Kei Islands off Tual; 20 m; 14 Apr 1922; sand 

20. Kei Islands, Doe Roe Bassin; 50 m; 14 Apr 1922; sand 

21. Kei Islands; 5.5°S, 132.78°E; 50 m; 14 Apr 1922; hard 

bottom, corals 

24. Kei Islands; 5.62°S, 132.93°E; 100 m; 15 Apr 1922; hard 

bottom 

26. Kei Islands; 5.63°S, 132.92°E; 20 m; 16 Apr 1922; sand 

27. Kei Islands, 2 miles N of Elat; 60 m; 17 Apr 1922; fine 

sand 

30. Kei Islands, between Doe Roa and Kei Doelah; 40 m; 18 

Apr 1922; sand, shells 

31. Kei Islands, Doe Roe Bassin; 50 m; 18 Apr 1922; sand 

33. Kei Islands; 5.517°S, 132.567°E; 285 m; 22 Apr 1922; 

sand 

36. Kei Islands, bay North of Noehoe-Roa; 35 m; 23 Apr 

1922; sand 

37. Kei Islands, Doe Roa Strait; 40 m; 23 Apr 1922; sand 

40. Kei Islands, North of Doe Roa; 20 m; 25 Apr 1922; sand 

42. Kei Islands; 5.58°S, 132.48°E; 225 m; 26 Apr 1922; mud 


coral 


46. Kei Islands; 5.79°S, 132.43°E; 250 m; 2 May 1922; clay, 

mud 

48. Kei Islands; 5.67°S, 132.35°E; 263 m; 3 May 1922; 

sandy mud 

52. Kei Islands; 5.77°S, 132.83°E; 352 m; 7 May 1922; mud 




shells 


mud 

60. Kei Islands, South of Doe Roa; 25 m; 14 May 1922; 

gravel, shells, lithothamnion 

61. Kei Islands, between Doe Roa and Kei Doelah; 50 m; 15 

May 1922; Bryozoans 


sand 

64. Sunda Strait; 5.85°S, 106.37°E; 35 m; 26 Jul 1922; sandy 

mud, shells 

65. Sunda Strait; 5.87°S, 106.28°E; 25 m; 27 Jul 1922; sand 


mud, shells 


68. Sunda Strait; 5.78°S, 106.28°E; 50 m; 27 Jul 1922; 

stones 


70. Kei Islands; 5.67°S, 106.35°E; 35 m; 28 Aug 1922; mud, 

shells 

71. Sunda Strait; 5.67°S, 106.13°E; 54 m; 28 Jul 1922; sand, 


72. Sunda Strait; 5.68°S, 105.95°E; 35 m; 28 Jul 1922; 


73. Sunda Strait; 5.95°S, 105.95°E; 30 m; 28 Jul 1922; sand, 

shells 

74. Sunda Strait; 6.05°S, 105.9°E; 30 m; 29 Jul 1922; mud 

81. Sunda Strait; 6.62°S, 105.45°E; 49 m; 29 Jul 1922; mud 


mud 


mud, pumice 

86. Sunda Strait; 5.9°S, 105.617°E; 31 m; 31 Jul 1922; mud, 

pumice 

90. Sunda Strait; 5.92°S, 105.5°E; 36 m; 1 Aug 1922; hard 

bottom 

91. Sunda Strait; 5.88°S, 105.45°E; 42 m; 1 Aug 1922; mud 



102. Krakotoa; 6.15°S, 105.47°E; 75 m; 3 Aug 1922; mud, 

pumice 

103. Sunda Strait; 6.08°S, 105.7°E; 52 m; 4 Aug 1922; sand, 

shells 

104. Sunda Strait; 5.87°S, 106.07°E; 38 m; 4 Aug 1922; 



106. Sunda Strait; 5.83°S, 106.27°E; 32 m; 5 Aug 1922; sand 


sand, stones 


sandy mud 


sandy mud 




sand, shells 


118. Sunda Strait; 5.9°S, 106.67°E; 27 m; 7 Aug 1922; sand, 

shells


Appendix 2 

List of marine hydoids recorded in Indonesian waters. The list is not necessarily complete. The numerous Stylasteridae are not 

included. For this taxon, see Boschma (1953, 1957), Cairns (1983), and Cairns & Hoeksema (1998). 

Some nominal species listed here are problematic and their inclusion does not mean that they are valid records or species. 

Species encountered in the collection of the Kei Island Expediton and described and discussed in this study are marked by a 

*. For the other species, one suitable reference is given, although the species may have been recorded by other authors too. 

Family Hydractiniidae 

Hydractinia granulata * new record 

Family Tubidendridae 

Balella mirabilis * new record 

Family Cordylophoridae 

Turritopsis nutricula this study 

Corydendrium corrugatum * new record 

Corydendrium parasiticum Vervoort 1941 

Family Bougainvilliidae 

Bougainvillia muscus Pictet 1893 

Garveia clevelandensis new record 

Family Eudendriidae 

Eudendrium capillare Vervoort 1941 

Eudendrium kirkpatricki * new record 

Eudendrium ramosum Stechow & Müller 1923 

Myrionema amboinense Pictet 1893 

Family Sphaerocorynidae 

Sphaerocoryne bedoti Pictet 1893 

Family Cladocorynidae 

Cladocoryne haddoni * new record 

Pteroclava crassa Pictet 1893 

Family Pennariidae 

Pennaria disticha * 

Family Solanderiidae 

Solanderia secunda * new record 

Family Tubulariidae 

Ralpharia neira Petersen 1990 

Ectopleura viridis * this study 

Family Campanulinidae 

Campanulina maduraensis Billard 1940b 

Campanulina panicula * new record 

Campanulina paucilaminosa Billard 1940b 

Egmundella sibogae Billard 1940a 

Modeeria rotunda Vervoort 1941 

Family Haleciidae 

Halecium dyssymmetrum Billard 1929b 

Halecium humile this study 

Halecium halecinum var. minor this study 

Halecium scalariformis Billard 1929b 

Halecium sessile Vervoort 1941 

Halecium sibogae Billard 1929b 

Hydrodendron dichotomum Billard 1929a 

Halecium spatulum Watson 2000 

255 

Hydrodendron sibogae * 

Mitrocomium simplex this study 

Family Hebellidae 

Hebella contorta Campenhausen 1896b 

Hebella corrugata Stechow & Müller 1923 

Hebella costata Stechow & Müller 1923 

Hebella dyssymetra Billard 1942b 

Hebella hartmeyeri Stechow & Müller 1923 

Hebella lata Pictet 1893 

Hebella laterocaudata Billard 1942b 

Hebella scandens Weltner 1900 

Hebella cylindrica Pictet 1893 

Family Lafoeidae 

Acryptolaria rectangularis * new record 

Acryptolaria angulata * new record 

Acryptolaria conferta * 

Cryptolarella abyssicola Campenhausen 1896b 

Lafoea dumosa * new record 

Zygophylax bifurcata Billard 1942a 

Zygophylax bifurcata * 

Zygophylax pinnata Campenhausen 1896b 

Zygophylax rufa * new record 

Zygophylax sibogae * 

Family Campanulariidae 

Clytia arborescens this study 

Clytia gracilis this study 

Campanularia raridenta Stechow & Müller 1923 

Clytia linearis * 

Clytia noliformis Pictet 1893 

Clytia sibogae Billard 1917 

Clytia trigona this study 

Obelia bidentata * 

Obelia geniculata Pictet 1893 

Family Sertulariidae 

Caminothujaria molukkana * 

Diphasia cauloatheca Billard 1925b 

Diphasia cristata Billard 1925b 

Diphasia densa Stechow & Müller 1923 

Diphasia digitalis * 

Diphasia minuta Billard 1925b 

Diphasia mutulata * 

Diphasia orientalis Billard 1925b 

Diphasia scalariformis * 

Diphasia thornelyi Billard 1925b 

Dynamena crisioides * 

Dynamena fissa Billard 1925b 

Dynamena heterodonta Billard 1925b 

Dynamena mertoni Stechow & Müller 1923 

Dynamena moluccana * 

Dynamena quadridenta Billard 1925b

256 

Geminella ceramensis * 

Hincksella cylindrica Billard 1925b 

Hincksella sibogae Billard 1925b 

Idiellana pristis * 

Salacia hexodon * 

Salacia punctagonangia * new record 

Salacia sibogae * 

Salacia sinuosa * 

Salacia tetracythara * 

Sertularella acutidentata Billard 1925b 

Sertularella catena Billard 1925b 

Sertularella crassa Billard 1925b 

Sertularella decipiens * 

Sertularella diaphana * 

Sertularella parva Billard 1925b 

Sertularella inconstans Billard 1925b 

Sertularella intricata Billard 1925b 

Sertularella keiensis Billard 1925b 

Sertularella minuscula Billard 1925b 

Sertularella quadridens * 

Sertularella robusta Billard 1925b 

Sertularia borneensis * 

Sertularia elongata Stechow & Müller 1923 

Sertularia loculosa * 

Sertularia malayensis * 

Sertularia trigonostoma * 

Sertularia turbinata * 

Symplectoscyphus clarkii Campenhausen 1896b 

Symplectoscyphus macrocarpa * 

Symplectoscyphus pedunculatus Billard 1925b 

Symplectoscyphus sibogae Billard 1925b 

Symplectoscyphus tropicus Billard 1925b 

Thuiaria abyssicola Billard 1925b 

Thuiaria articulata Stechow & Müller 1923 

Family Thyroscyphidae 

Thyroscyphus bedoti this study 

Thyroscyphus fruticosus * 

Thyroscyphus sibogae * 

Thyroscyphus torresii * 

Family Syntheciidae 

Synthecium flabellum * new record 

Synthecium elegans Billard 1925b 

Synthecium megathecum Billard 1925b 

Synthecium dentigerum Billard 1925b 

Synthecium orthogonium * 

Synthecium campylocarpum * 

Synthecium samauense * 

Family Halopterididae 

Antennella campanulaformis * new record 

Antennella secundaria * 

Antennella sibogae Billard 1913 

Antennella varians Billard 1913 

Halopteris alternata Billard 1913 

Halopteris campanula Billard 1913 

Halopteris concava Billard 1913 

Halopteris crassa Billard 1913 

Halopteris diaphragmata Billard 1913 

P. SCHUCHERT 

Halopteris jedani Billard 1913 

Halopteris peculiaris Billard 1913 

Halopteris plagiocampa * 

Halopteris polymorpha Billard 1913 

Monostaechas simplex Billard 1913 

Monostaechas sibogae Billard 1913 

Family Plumulariidae 

Nemertesia indivisa * 

Nemertesia ramosa Billard 1913 

Nemertesia singularis Vervoort 1941 

Plumularia badia * 

Plumularia campanuloides Billard 1913 

Plumularia crater Billard 1913 

Plumularia habereri * 

Plumularia insignis Billard 1913 

Plumularia orientalis Billard 1913 

Plumularia scabra * 

Plumularia setacea Billard 1913 

Plumularia spiralis Billard 1913 

Plumularia strictocarpa Pictet 1893 

Plumularia strobilophora Billard 1913 

Plumularia stylifera Stechow & Müller 1923 

Polyplumaria cornuta * 

Polyplumaria kossowskae Billard 1913 

Polyplumaria sibogae Billard 1913 

Polyplumularia bedoti Billard 1913 

Sibogella erecta * 

Family Kirchenpaueriidae 

Kirchenpaueria halecioides Pictet 1893 

Kirchenpaueria ventruosa Billard 1913 

Family Aglaopheniidae 

Aglaophenia cupressina * 

Aglaophenia laxa Billard 1913 

Aglaophenia postdentata Billard 1913 

Aglaophenia sibogae * 

Cladocarpus keiensis* new species 

Cladocarpus multiapertus Billard 1913 

Cladocarpus siboga Billard 1913 

Gymnangium allmani Billard 1913 

Gymnangium gracilicaule * 

Gymnangium haswellii Billard 1913 

Gymnangium hians Billard 1913 

Gymnangium longicorne * 

Lytocarpia angulosa * 

Lytocarpia brevirostris Billard 1913 

Lytocarpia delicatula * 

Lytocarpia furcata Vervoort 1941 

Lytocarpia orientalis * 

Lytocarpia perarmata * 

Lytocarpia phyteuma * 

Macrorhynchia balei * 

Macrorhynchia philippina * 

Macrorhynchia phoenicea * 

Macrorhynchia sibogae Billard 1913 

Macrorhynchia singularis * 

Monoserius pennarius *

Hydroids (Cnidaria, Hydrozoa) of the Danish expedition to

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