PRELIMINARY INSIGHTS INTO THE PHYLOGENY AND SPECIATION OF SCALESIA (ASTERACEAE), GALÁPAGOS ISLANDS Jeremy D. Blaschke Roger W. Sanders Bryan College # 7071 721 Bryan Dr. Dayton, Tennessee 37321, U.S.A. jblaschke0998@bryan.edu Bryan College # 7802 721 Bryan Dr. Dayton, Tennessee 37321, U.S.A. rsanders@bryan.edu ABSTRACT Scalesia Arn. (Asteraceae: Heliantheae) is a woody genus of fifteen species endemic to the Galápagos Islands. Morphological, distribution, and habitat data pertinent to speciation patterns in Scalesia were extracted from the literature and selected auxiliary specimens. All species of Scalesia, Pappobolus S.F. Blake, and Simsia Pers., along with selected species of Viguiera Kunth, were subjected to phylogenetic analysis (63 characters in 78 taxa). Homoplasy and incongruence among resulting trees prevented resolution of relationship and comparison of speciation events relative to its sister-group. Morphologically, species throughout these genera are marked primarily by homoplastic apomorphies. Based on broad characterization of habitats, morphological divergence (except for arborescence) and habitats appear to be poorly correlated. Sampling for future studies should be extended to include other groups in the derived Helianthinae. RESUMEN Scalesia Arn. (Asteraceae: Heliantheae) es un género leñoso de quince especies, endémico de las Islas Galápagos. Los datos morfológicos, de distribución y de hábitat relativos a los patrones de especiación en Scalesia se obtuvieron de la bibliografía y de especimenes auxiliares seleccionados. Todas las especies de Scalesia, Pappobolus S.F. Blake, y Simsia Pers., junto con algunas especies de Viguiera Kunth, fueron objeto de un análisis filogenético (63 caracteres en 78 taxa). La homoplasia e incongruencia entre los árboles resultantes impidió la resolución de parentesco y comparación de eventos de especiación relativa a su grupo hermano. Morfológicamente, las especies de estos géneros se distinguen primariamente por apomorfías homoplásticas. Basados en la amplia caracterización de los hábitats, la divergencia morfológica (excepto la arborescencia) y los hábitats parecen estar pobremente correlacionadas. El muestreo para futuros estudios debe ampliarse para incluir otros grupos de Helianthinae derivadas. INTRODUCTION Scalesia Arn. (Asteraceae: Heliantheae: Helianthinae) comprises fifteen species, all endemic to the Galápagos Islands. Howell (1941) accepted 18 species in four sections and related it to the Ecliptinae Lessing. Based on extensive field study, Eliasson (1974) recognized only 14 species, avoided the use of sections, discussed aspects of character evolution, and placed the genus in the Helianthinae Dumort. Hamann and WiumAndersen (1986) described an additional species. Recent studies on Scalesia have focused on intergeneric relationships (Schilling et al. 1994; Spring et al. 1999; Panero 2007), chemical diversity (Adsersen & Baerheim Svendsen 1986; Spring et al. 1997, 1999; Petersen et al. unpubl.), anatomy (Carlquist 1982), autecology (Itow 1995; Kitayama & Itow 1999; Hamann 2001), adaptive reproductive strategies (McMullen & Naranjo 1994; Nielsen et al. 2002, 2007), and population structure (Nielsen et al. 2003; Nielsen 2004). Chloroplast DNA restriction site analysis suggests that Scalesia belongs to a group of specialized genera, the “derived Helianthinae,” that are embedded within a derived clade of Viguiera Kunth (Schilling et al. 1994). Viguiera, whose taxonomy has been unresolvable on morphological grounds, appears as a paraphyletic assemblage basal to all other genera in the Helianthinae on the basis of cpDNA restriction sites and internal transcribed spacer (ITS) sequences of nuclear ribosomal DNA (Schilling & Jansen 1989; Schilling & Panero 2002). In an analysis in which S. pedunculata Hook.f. and several species of Pappobolus S.F. Blake were sampled (Schilling et al. 1994), Scalesia and Pappobolus were sister groups, and the next closest clade consisted of Simsia Pers. plus Viguiera ser. Pinnatilobatae S.F. Blake. However, the authors noted problems with interpretation of the three restriction sites synapomorphic for Scalesia and Pappobolus and concluded, “Thus, the relative relationships among Scalesia, Pappobolus, Simsia J. Bot. Res. Inst. Texas 3(1): 177 –191. 2009 178 Journal of the Botanical Research Institute of Texas 3(1) and Viguiera ser. Pinnatilobatae are not well resolved by these data.” Indeed, subsequent work has shown that chloroplast restriction sites, chloroplast genes, and ITS regions lack sufficient variation to resolve relationships in the derived Helianthinae (Schilling & Panero 1996, 2002; Petersen et al. unpubl.). However, recent analyses using external transcribed spacer (ETS) regions did find sufficient diversity to resolve species of Helianthus (Timme et al. 2007), a member of the derived Helianthinae, as well as species in other genera of the Heliantheae, such as Montanoa (Plovanich & Panero 2004). Our interest is primarily in patterns of diversification, homoplasy, speciation rates, and degree of adaptation using Scalesia because it is the most speciose endemic angiosperm genus in the Galápagos. It is of interest that homoplasy among morphological characters of Simsia species prevented Spooner (1990) from publishing a cladistic analysis in his monograph. Likewise, Panero (1992) chose not to include phylogeny in his monograph of Pappobolus, instead recognizing only phenetic groupings. Thus, notable amounts of unanalyzed data are available in the literature for addressing the issue of homoplasy across Scalesia and relations. While it is our hope in the future to sample ETS regions in Scalesia species to determine their applicability in phylogenetic analysis, as well as use molecular phylogenies in investigating issues of interest to us, our goal here is to mine the existing pertinent morphological and ecological data that are available in the literature to provide a comparative context for later molecular studies. That is, we seek to provide insights into: 1) sister-group and intrageneric relationships of Scalesia, 2) homoplastic traits, 3) relative amounts of speciation per clade, and 4) directions for future molecular sampling. We anticipate that phylogenetic analysis of morphology may not yield consistent assessments of relationships or be congruent with molecular phylogenies (for example, see Plovanich and Panero [2004] concerning homoplasy in morphological taxonomic criteria in the Heliantheae). However, that result is not certain, for the hand-calculated Wagner parsimony networks of morphological data of Dendroseris and Robinsonia (Sanders et al. 1987), two other island endemics of the Asteraceae (Lactuceae and Senecioneae, respectively), did prove to be congruent with later molecular phylogenies (Crawford et al. 1992; Sang et al. 1995). METHODS Data.—Taxon sampling is based on the sister-group conclusions and Figure 1 of Schilling et al. (1994) and availability of supplemental specimens at the Botanical Research Institute of Texas and Bryan College. Morphological traits, coded as binary and multistate unordered characters, were extracted from published monographs of Pappobolus (Panero 1992), Scalesia (Eliasson 1974; Hamann & Wium-Andersen1986), Simsia (Spooner 1990), and species representing Helianthus L. (Schilling 2006), Viguiera sect. Maculatae (S.F. Blake) Panero & Schilling (Panero & Schilling 1988), and the outgroup Bahiopsis Kellogg (Schilling 1990). Selected dried specimens were consulted to verify codings obtained from the literature, supply missing data, and score representative species from Viguiera ser. Grammatoglossae S.F. Blake and ser. Pinnatilobatae (Table 1). Characters were chosen to maximize distinctions within Scalesia, Pappobolus, and Simsia and scored accordingly in the remaining taxa (Table 2), resulting in a number of characters being coded as polymorphisms. The compiled data constitute 63 characters in 78 species (Appendix). Phylogenetic Analysis.—Parsimony analysis was conducted using PAUP* 4.0b10 (Swofford 1998). Heuristic searches were made with character optimization set to both accelerated and delayed transformation and with the following options: character weighting equal, 10 rounds of random addition sequence with 100 trees held at each addition, branch swapping by tree-bisection, MulTrees in effect, MaxTrees=100,000. Bootstrap analysis (10,000 replicates) was conducted using accelerated transformation by heuristic search with 10 trees held at each addition step. A final heuristic search, in which the majority-rule consensus tree from the bootstrap analysis was input for branch swapping only, was conducted using accelerated transformation with options as above. Based on the strict consensus tree from the first heuristic search, a reduced matrix of only the ancestral nodes of the outgroup, Helianthus, Pappobolus, Simsia, and Viguiera grammatoglossa + V. stenophylla; the remaining Viguiera species; and the species of Scalesia was generated. This matrix was subjected to a branch-and-bound search (options: accelerated transformation, equal weighting, MulTrees in effect, furthest addition sequence) and bootstrap analysis as above. Blaschke and Sanders, Phylogenetics and speciation of Scalesia 179 TABLE 1. Herbarium specimens consulted to supplement and verify data in literature. BRYAN is not yet officially recognized by Index Herbariorum but is used provisionally to designate the Henning Natural History Museum of Bryan College. Taxon Specimen Locality Herbarium S. White 5042 Mahler & Thieret 5440 Mexico: Baja, California. La Paz USA: Arizona: Maricopa Co.: Sagauro Lake SMU SMU H. tuberosus L. W. L. Henning Acc. No. B 802 G. Varga Acc. No. B 1794 W. L. Henning Acc. No. B 804 USA: Missouri: Boone Co.: W of Columbia USA: Tennessee: Rhea Co. USA: Missouri: Boone Co.: S of Columbia BRYAN BRYAN BRYAN Pappobolus P. acutifolius (S.F. Blake) Panero P. matthewsii (Hochr.) Panero P. robinsonii Panero P. steubelii (Hieron.) Panero Panero & Galán 1399 J. Panero 1353 Panero & Sánchez 1225 Panero et al. 932 Perú: Ancash: Caráz Perú: Amazonas: Pedro Ruiz Perú: Cajamarca: Celendin Perú: Cajamarca: Chalhuayaco BRIT BRIT BRIT BRIT Scalesia S. affinis Hook.f. S. helleri B.L. Rob. S. stewartii L. Riley S. villosa A. Stewart Mears 5296 Mears 5494 Mears 5556 Mears 5226 Ecuador: Galápagos: Floreana Ecuador: Galápagos: Santa Fe Ecuador: Galápagos: Bartolomé Ecuador: Galápagos: Gardner BRIT BRIT BRIT BRIT S. eurylepsis S.F. Blake S. foetida (Cav.) S.F. Blake S. fruticulosa (Spreng.) S.F. Blake S. holwayi S.F. Blake A. Cronquist 9611 J. Rodriguez 64 U. Waterfall 16660 U. Waterfall 14300 Yen & Estrada 6479 King & Guevara 5817 R. M. King 7337a SMU SMU SMU SMU BRIT SMU BRIT S. sanguinea A. Gray C. G. Pringle 11513 Mexico: Michoacán: La Piedad Mexico: Nuevo León: Vallecillo Mexico: Coahuila: Sabinas Mexico: San Luis Potosí: Ciudad de Valles Mexico: Chihuahua: Presa Chihuahua Colombia: Cundinamarca. Chipaque Guatemala: Alta Verapaz: San Cristóbal Verapaz Mexico: Jalisco: Guadalajara Viguiera ser. Grammatoglossae V. cordifolia A. Gray J. Cornelius 227 D. S. Correll 15006 V. grammatoglossa DC. J. Rzedowski 34497 USA: Texas: Brewster Co.: Black Gap WMA USA: Texas: Jeff Davis Co.: Davis Mts. Mexico: Oaxaca. Chilapa de Díaz SMU SMU VDB Viguiera sect. Maculatae V. adenophylla S.F. Blake E. Estrada 1889 Mexico: Nuevo León. Iturbide BRIT Viguiera ser. Pinnatilobatae V. stenoloba S.F. Blake A. Krings 288 USA: Texas: Presidio Co.: Big Bend Ranch State Park Mexico: Edo. Coahuila. Mun. San Pedro USA: Texas: Brewster Co.: Big Bend National Park BRIT Bahiopsis B. deltoidea A. Gray B. parishii Greene Helianthus H. annuus L Simsia S. amplexicaulis (Cav.) Pers. S. calva A. Gray Nee & Diggs 25354 A. Treverse 2215 SMU BRIT BRIT Bayesian analysis was conducted using MrBayes v3.1.2 (Huelsenbeck & Ronquist 2001) on both the full and the reduced matrices using the default settings of the standard discrete evolutionary model. Analysis of the full matrix was run for 200,000,000 generations and sampled once every 100,000 generations; the reduced matrix was run for 400,000 generations and sampled every 100 generations. Habitat Characterization.—Geographic distributions and habitat features were estimated from Cronquist (1971), Eliasson (1976), Hamann and Wium-Andersen (1986), and personal observation of one of us (RWS). 180 Journal of the Botanical Research Institute of Texas 3(1) TABLE 2. Characters and character states used in data matrix (Appendix). Character states are unordered. 1. Habit 0: shrub, 1: tree, 2: suffrutescent perennial, 3: perennial herb, 4: annual 2. Hair type presence 0: unspecialized pubescent, 1: villous to lanate, 2: scabrous or strigose 3. Glandular trichomes 0: absent, 1: present 4. Twig pubescence color 0: white to gray, 1: yellow or green 5. Leaf phyllotaxy 0: alternate, 1: opposite 6. Leaf heterchrony 0: inflorescence leaves ± size of cauline lvs., 1: lvs. partially or gradually reducing into inflor., 2: lvs. much reducing into inflor. 7. Leaf outline 0: ovate, 1: lanceolate, 2: cordate, 3: triangular, 4: elliptic, 5: linear-oblong 8. Leaf margin lobing 0: unlobed, 1: lobed 1/4 to midrib, 2: lobed 1/2 to midrib, 3: lobed 3/4 to midrib, 4: regularly deeply lobed nearly to midrib 9. Leaf margin serration 0: completely entire, 1: crenate or serrulate, indistinctly toothed, 2: distinctly serrate 10. Leaf margin orientation 0: flat, 1: revolute 11. Leaf adaxially strigose 0: not strigose, scabrous, or sericeous, 1: moderately strigose, scabrous, or sericeous, 2: densely strigose, scabrous, or sericeous 12. Leaf abaxially strigose 0: not strigose, scabrous, or sericeous, 1: moderately strigose, scabrous, or sericeous, 2: densely strigose, scabrous, or sericeous 13. Leaf abaxially lanate 0: not villous or lanate, 1: moderately villous or lanate, 2: densely villous or lanate 14. Leaf surface reflectance, adaxially 0: dull, 1: shiny 15. Leaf texture 0: herbaceous/chartaceous, 1: leathery, 2: thinly membranous 16. Leaf venation 0: triplinerved, 1: pinninerved 17. Leaf midrib position adaxially 0: level or above surface, 1: sunken below surface 18. Petiole shape 0: unwinged, 1: wing tapering in apex, 2: wing tapering above base, 3: wing broad to basal insertion, 4: winged at base only 19. Petiole length 0: 0–9 mm, 1: >10 mm 20. Inflorescence reiteration 0: monochasial, 1: dichasial 21. Head arrangement 0: more/less solitary, 1: open panicle, 2: tightly aggregate panicle 22. Head size (w/o rays) 0: very large >30 mm, 1: large 15–30 mm, 2: moderate 7–15 mm, 3: small <7 mm 23. Involucre shape 0: campanulate-subcylindric, 1: urceolate-hemispheric 24. Phyllary series 0: 3–4, 1: 2, 2: (4–)5–6 25. Phyllary shape 0: oblong to obtrullate, 1: narrowly elliptic, 2: lanceolate, 3: subulate-attenuate, 4: ovate 26. Phyllary, outer series, shape 0: not spatulate, 1: spatulate 27. Phyllary size to florets 0: subtending florests, 1: overtopping florets 28. Phyllary size ratio, outer/inner 0: outer ± inner, 1: outer < 2/3 inner 29. Phyllary color 0: normal green, 1: stramineous ± with green stripes, 2: blackish green, 3: purple 30. Phyllary consistency 0: scale-like, 1: foliaceous 31. Phyllary pubescence density 0: revealing surface, 1: obscuring surface 32. Phyllary margin, cilia 0: without cilia, 1: ciliate 33. Phyllary tip shape 0: blunt or abruptly acute, 1: acuminate, long acute 34. Phyllary tip orientation 0: erect or appressed, 1: reflexed or spreading 35. Phyllary base thickness 0: unthickened, herbaceous, 1: base slightly thickened indurate, 2: base conspicuously thickened indurate 36. Ray presence 0: absent, 1: present in full complement, 2: present in part 37. Ray orientation 0: spreading, 1: strongly reflexed or recurved 38. Ray ligule length 0: <1.5 cm, 1: 1.5–3.0 cm, 2: > 3 cm 39. Ray apex fusion 0: shallowly 2-3 toothed, 1: deeply 2-3 notched/lobed, 2: irregularly, barely fused or lipped 40. Ray ovary shape 0: ovoid/lenticular/fusiform, 1: linear 41. Palea length 0: about equalling phyllaries, 1: protruding above phyllaries, 2: shorter than phyllaries 42. Palea apex pubescence 0: glabrous, 1: pubescent 43. Palea segmentation 0: lacking, 1: shallow, 2: deep 44. Palea segments, shape 0: elliptic, 1: triangular, 2: ovaterounded, 3: subulate, 4: oblong-ligulate 45. Palea segments, orientation 0: erect, 1: diverging or reflexed, 2: strongly overlapping, 3: inflexed or hooded 46. Palea segments, central one 0: equal to laterals, 1: much longer than laterals 47. Disk corolla color 0: yellow to orange, 1: brown, 2: pale yellow, 3: white, 4: pink, 5: deep purple 48. Disk corolla tube to throat length ratio 0: ~3–4, 1: ~5–10, 2: ~1 49. Disk corolla tube pubescence 0: glabrous, 1: puberulent 50. Disk corolla throat pubescence 0: glabrous, 1: puberulent 51. Disk corolla lobes abaxially 0: without dark pigment, 1: with black pigment, 2: with purple pigment 52. Anther color 0: yellow, 1: black, 2: (yellow) purple distally, 3: maroon or brown 53. Anther appendix color 0: stramineous, 1: all or part black, 2: white 54. Style branch color abaxially 0: without black pigment, 1: with black pigment 55. Style branch apex 0: deltate, 1: attenuate 56. Style branch appendage 0: absent, 1: present 57. Achene length 0: < 3 mm, 1: 3–5 mm, 2: > 5 mm 58. Achene pubescence 0: glabrous, 1: sericeous 59. Achene compression 0: biconvex-lenticular, 1: laterally flat but slightly biconvex, 2: strongly lat. flattened, 3: terete or trigonous 60. Pappus development 0: absent, 1: callous ring only, 2: awns and/or scales 61. Pappus, no. awns 0: 0, 1: 1 (often small), 2: 2, 3: multiple 62. Pappus, intervening scales 0: absent, 1: present 63. Pappus persistence 0: persistent, 1: caducous Blaschke and Sanders, Phylogenetics and speciation of Scalesia 181 RESULTS Sister-group relationships.—The first two heuristic searches (random-addition with accelerated vs. delayed character transformations) resulted in 100,000 shortest trees each (442 steps). These and their strict consensus trees were partially incongruent with the majority-rule tree of the bootstrap analysis. In the delayed transformation search, Viguiera adenophylla was sister to all other ingroup taxa, and Pappobolus was paraphyletic with P. ecuadoriensis sister to all remaining taxa. Of these, one clade contained P. sagasteguii, a subclade of V. stenoloba + Scalesia, and a subclade containing the remaining Viguiera species, Helianthus, and Simsia as monophyletic genera. The other clade contained all remaining species of Pappobolus. The accelerated transformation search resulted in V. adenophylla as above but the remaining ingroup taxa constituted five clades in an unresolved polytomy: V. cordifolia, Helianthus, Scalesia, Simsia, and one having a monophyletic Pappobolus sister to V. grammatoglossa + V. stenoloba. The third heuristic search (bootstrap majority-rule tree input and branches swapped) resulted in all 100,000 trees being congruent with the bootstrap analysis, though one step longer (443) than the trees from the first two searches. In the strict consensus tree of this analysis (Fig. 1), the ingroup formed three major clades. A monophyletic Pappobolus was sister to the remaining ingroup taxa. Of these, one clade consisted of V. adenophylla and Scalesia as sister groups. The other clade contained a tetrachotomy: Simsia, Helianthus, V. cordifolia, and V. grammatoglossa + V. stenoloba. The Bayesian majority-rule consensus tree (analysis final average standard deviation 0.0078) added yet another possible arrangement. Of the ingroup taxa, Scalesia + V. adenophylla were sister to the remainder, which formed a polytomy: V. grammatoglossa, V. stenoloba, nine species of Pappobolus, a clade with all the remaining Pappobolus, and a clade consisting of V. cordifolia, Helianthus, and Simsia. In all of the consensus trees, Simsia was completely unresolved or nearly so, and Pappobolus contained two to three large sets of unresolved species. Scalesia was reasonably well resolved but its topology differed among trees. All heuristic searches found the arboreous species as a resolved clade (S. cordata A. Stewart, S. microcephala B.L. Rob., S. peduculata basal), the lobe-leaved species (S. baurii Robinson & Greenman, S. helleri Robinson, S. incisa Hook.f., S. retroflexa Hemsl.) as a partially or fully resolved clade, the three species with elongate phyllaries (S. atractyloides Arn., S. stewartii L. Riley, S. villosa A. Stewart basal) as a grade or clade, and a clade of S. divisa Andersson + S. gordilloi O.J. Hamann & Wium-And. In two searches the arboreous clade was sister to the remainder with the elongate-bracted clade deeply imbedded; in the third the elongate-bracted group was a basal grade with the arboreous clade deeply imbedded. In the Bayesian majority rule tree, Scalesia was an eight-way polytomy of the arboreous, elongate-bracted, and lobe-leaved clades, S. affinis Hook.f., S. aspera Andersson, S. crockeri J.T. Howell, S. divisa, and S. gordilloi. Branch-and-bound analysis of the reduced matrix produced 13 trees of equal length (163 steps). In the strict consensus tree (Fig. 2), V. adenophylla was sister to the other ingroup taxa, which formed a tetrachotomy: Scalesia, Helianthus, Simsia + V. cordifolia, and Pappobolus + the V. grammatoglossa-stenophylla ancestor. In Scalesia, the arboreous clade (unresolved) was sister to the remainder which formed a polytomy of S. affinis, S. aspera, S. crockeri, S. divisa, S. gordilloi, a partially resolved clade of the lobe-leaved species, and a resolved elongate-bracted clade. However, the Bayesian majority rule tree (analysis final average standard deviation 0.0070) of the reduced matrix differed by being nearly identical to one of the most parsimonious branch-and-bound trees (Fig. 2) except that 1) the arboreous species formed a basal grade with S. cordata + S. microcephala sister to the remaining species, 2) there was no resolution among S. affinis, S. aspera, S. crockeri and the remaining clades, and 3) S. retroflexa was basal to the other members of the lobe-leaved clade. Apomorphies and homoplasy.—In one of the 100,000 equally parsimonious trees from the third heuristic search the composite consistency index (CI) was 0.24 (excluding two uniformative characters), the rescaled CI (RC) was 0.17, and the retention index (RI) was 0.71. In this tree, the only synapomorphies of Scalesia with a consistency index over 0.4 were ray florets absent and anthers black. The only comparable synapomorphy for Pappobolus was anthers yellow and for Simsia, phyllaries not thickened at base and achenes strongly laterally flattened. The composite CI of the branch-and-bound trees (Fig. 2) was 0.49 (including only 51 informative char- 182 Journal of the Botanical Research Institute of Texas 3(1) FIG. 1. Strict consensus tree of third heuristic search (branch-swapping of input bootstrap majority-rule tree) of full data matrix, based on 100,000 equally parsimonious trees. Bold numbers above branches indicate bootstrap values; italic numbers below branches indicate Bayesian posterior probabilities. Generic abbreviations: B=Bahiopsis, H=Helianthus, P=Pappobolus, Sc=Scalesia, Si=Simsia, V=Viguiera. Blaschke and Sanders, Phylogenetics and speciation of Scalesia 183 FIG. 2. One of 13 equally parsimonious trees obtained from branch-and-bound analysis of Scalesia. Bold numbers above branches indicate bootstrap values; italic numbers below branches indicate Bayesian posterior probabilities. Dashed lines indicate branches that are collapsed in the resulting strict consensus tree. Generic abbreviations are as in Figure 1. Numbers of apomorphies on branches of Scalesia by class as follows: solid dot = unique (synapomorphies/autapomorphies), open circles = homoplasy restricted to species of Scalesia, box = homoplastic between Scalesia and another genus, box with circle = homoplastic both within Scalesia and with external genus. 184 Journal of the Botanical Research Institute of Texas 3(1) acters), the RI 0.66, and RC 0.37. In this tree, the synapomorphies for Scalesia supported by a consistency index of 0.4 or greater included: capitula 15-30 cm diameter; involucre hemispheric to urceolate; phyllaries oblong to obtrullate and erect/appressed; ray absent but, when present deeper within the clade, reflexed with irregularly fused lobes; paleae deeply segmented; corollas white; anther appendices white; and achenes glabrous. Black anthers, instead, appeared to be synapomorphic for the ingroup minus V. adenophylla. The third heuristic search of the full matrix resulted in only six characters that were completely consistent: four involved autapomorphies (or synapomorphies for species pairs), whereas only three involved synapomorphies of significant clades. Eleven homoplastic characters had consistency indices of 0.5 or higher. Four of these (phyllary base thickening, ray presence, fusion of ray lobes, and shape of palea segments) were parallelisms or reversals within Scalesia; only two (growth habit, orientation of palea segments) were parallelisms between species of Scalesia and other genera. Forty-six characters had consistency indices lower than 0.5, of which 30 appeared in both Scalesia and other genera, 15 in only other genera, and only one (ratio of corolla tube to limb lengths) just in Scalesia. The branch-and-bound matrix had only 55 variant characters. Sixteen were consistent, and, of these, eleven involved synapomorphies of significant clades. Twenty-five characters were homoplastic with a consistency index of 0.5 or higher including nine appearing within Scalesia and six in Scalesia and related genera. Only 14 characters were below the 0.5 consistency index level with only one restricted to species of Scalesia (as above), only one outside of Scalesia, and the remaining 12 appearing in both Scalesia and other genera. Geographic distributions and ecology.—All species except Scalesia affinis, which is sympatric with S. aspera, S. crockeri, S. helleri, S. retroflexa, and S. villosa, are narrowly allopatric or parapatric (Fig. 3). Some have disjunct populations occurring on separate islands. All the arboreous species (S. pedunculata, S. cordata, and S. microcephala) are found in the moist forest zone in mid to upper elevation and are geographically isolated from each other. Scalesia affinis, the only species with consistently radiate capitula, has the widest distribution and occupies the widest range of habitats; occurring most commonly in the arid zone, it ranges from coastal to lower parts of the moist forest zone. All remaining species are found in the low elevation (littoral, arid, and dry forest zones) (Table 2). Due to overlap of preferences, there appears to be little habitat differentiation among these species. Only the rare species S. crockeri and S. retroflexa are known only from littoral sites. Other species (e.g., S. atractyloides; Mauchamp et al. 1998) are restricted to cliffs due to grazing by feral goats but historically ranged over more littoral and arid sites. DISCUSSION Phylogenetic relationships.—The present results support the monophyly of Scalesia, Simsia, and Helianthus. Although molecular data (Schillling et al. 1994) support Pappobolus as monophyletic, the present data are equivocal in that regard, in some cases placing Scalesia, Simsia, Helianthus, and associated Viguiera species within a paraphyletic Pappobolus. Morphological data do not resolve the sister-group relationships of Scalesia, leaving open the possibility that Scalesia is sister to a group of Viguiera species or that Scalesia arose more or less simultaneously with Simsia, Helianthus, and Pappobolus (with any associated Viguiera species). As Viguiera sect. Maculatae is basal among the derived Helianthinae based on DNA restriction site and ITS data (Schilling & Jansen 1989; Schilling et al. 1994; Schilling & Panero, 1994, 1996, 2002), the sister-group placement of Scalesia and V. adenophylla in some results is due possibly to experimental error in coding or identification. Furthermore, Schilling and Panero’s (1996) molecular analysis suggests that Tithonia Desf. ex Gmelin, Viguiera subg. Amphilepis S.F.Blake, and V. sect. Paradosa S.F.Blake are closer to Pappobolus than is Simsia and should be considered as potential sister groups of Scalesia. Within Scalesia there is general support for the lobe-leaved, arboreous, elongate-bracted, and divisagordilloi clades. Because the arboreous clade did not receive support from a minority of analyses, it is interesting that Eliasson (1974) considered S. pedunculata to have developed arborescence convergently with S. cordata and S. microcephala. If all variant trees based on the various analyses preformed are considered, the only clades receiving total support are the lobe-leaved clade and a terminal clade of S. atractyloides and S. Blaschke and Sanders, Phylogenetics and speciation of Scalesia 185 FIG. 3. Distribution of Scalesia species, estimated from literature, including historically known ranges. Fine stippling = Scalesia affinis, course stippling = lobe-leaved clade; cross hatching = arboreous clade, vertical lines = elongate-bracted clade, solid dark gray = divisa-gordilloi clade; solid light gray = remaining species. stewartii, more in line with Eliasson’s conclusions. Within the lobe-leaved clade, there is total support for S. baurii and S. incisa as a clade, but only partial support for S. helleri + S. retroflexa. In this case, these clades and all remaining species would radiate from a basal polytomy. If, indeed, Scalesia is an example of radiation by the rapid dispersal of founder populations from an initial colonizer, an unresolved basal polytomy may portray more accurately the history of Scalesia than any of the less-supported but more-resolved trees. Homoplasy.—Obviously, the degree of resolution of the particular cladogram examined will affect the level of homoplasy among taxa. Because the branch-and-bound analysis resulted in 13 equally parsimonious well-resolved trees and the comparison of all analyses suggest a minimally resolved polytomy within Scalesia, the level of homoplasy discussed is based on the branch-and-bound consensus tree, which is intermediate in resolution (Fig. 2). Scalesia itself is delimited by five synapomorphies and 11 homoplastic apomorphies (two among Scalesia species, five with external taxa, and four occurring both inside and outside Scalesia). Of the 15 species and 6 clades in Scalesia, only 9 are delimited by unique apomorphies. Of the 90 total character-states apomorphic for clades and species, 14 (16%) are unique, 42 (46%) are homoplastic only within Scalesia, 9 (10%) are homoplastic only between Scalesia and external taxa, and 25 (28%) are homoplastic between Scalesia taxa as well as with external taxa. It will be of interest to see the level of morphological homoplasy on DNA-sequence trees when these become available. 186 Journal of the Botanical Research Institute of Texas 3(1) TABLE 3. Characterization of habitats of Scalesia species, estimated from the literature. Moist Forest Zone cordata microcephala pedunculata affinis villosa atractyloides stewartii incisa baurii retroflexa helleri gordilloi divisa aspera crockeri x x x x Littoral Zone x x x x ? ? x x x x x Arid Zone x x x x x x x x x x Dry Forest Zone Volcanic Soil x x x x x x ? x x x Lava Gravel x x x x ? x x x x x x x x x Fissured Lava x x x x x x x x x The characters that (at least some states of which) are not homoplastic in Scalesia include tree habit, leaf outline, leaf marginal lobing, dense villous hairs on abaxial leaf and phyllary surfaces, petiole shape, phyllary shape, ray orientation, palea segment shape and orientation, disk corolla color, disk corolla shape, anther appendage color, achene pubescence, and pappus development. However, all other characters and some states of the above are homoplastic. Some interesting examples include: 1) the presence of villous hairs in S. villosa and Pappobolus; 2) more or less solitary capitula of most species of Scalesia and Viguiera grammatoglossa and V. stenoloba; 3) multiple changes in size of capitula in Scalesia; 4) phyllary shape in S. crockeri and Helianthus; 5) palea length in S. microcephala, the elongate bracted clade, and Pappobolus; 6) glabrous paleae in S. aspera, S. baurii, S. incisa, S. microcephala, and Pappobolus; 7) length of the central lobe of the paleae in S. affinis, S. crockeri, S. microcephala, S. villosa; 8) disk corolla tube length in S. affinis, S. baurii, S. stewartii, the lobe-leaved clade, and Viguiera adenophylla; and 9) glabrous disk corolla tubes in S. affinis, S. aspera, S. villosa, the arboreous clade, and Simsia. Many of these characters are associated with the palea and corolla structure. According to Plovanich and Panero (2004), such characters associated with reproductive success should be convergent in the Heliantheae due to strong selection pressures. Whether this will be true in Scalesia remains to be investigated using molecular data sets. In regard to the presence of rays in certain species of Scalesia, Eliasson (1974) concluded that rays were lost in the ancestor of Scalesia, regained as scattered bilabiate disk corollas in the lobed-leaved species, and regained as nearly typical rays in S. affinis. His hypothesis is supported by the results presented here. If the affinis-type rays are the end of a character transformation involving the bilabiate disk corollas or are a reversal to true rays, then this constitutes an additional homoplastic trait. Presumably rays increase insect pollination and should be selected for on islands as the insect fauna diversifies, as suggested by the wider distribution of S. affinis. However, the addition of artificial rays to S. pedunculata did not increase its fitness (Nielsen et al. 2002). Therefore it is not clear that this character has high adaptive value in Scalesia. Despite the species and clades of Scalesia being delimited primarily by unique combinations of homoplastic character states as opposed to unique apomorphies, the species all appear to be distinct. Moreover, the full data set suggests that there is a real lack of morphological synapomorphy/autapomorphy within the continental genera because many species groups and species are likewise defined only by unique combinations of homoplastic characters states, not unique states. Distribution in relation to phylogenetic results and homoplasy.—Because the oldest islands in the archipelago are in the southeast and the youngest in the west and northwest, correlation of geology with the cla- Blaschke and Sanders, Phylogenetics and speciation of Scalesia 187 dograms is not straightforward. If the species diverged from east to west, the basal split should produce a group of eastern species with the western species the most derived. However, the main split is between lowland and upland species. This may suggest that the lowland species diverged after the older islands from San Cristóbal west to Santiago were already in place and the lineage ancestors were able to disperse among islands easily. Among the upland species, Scalesia microcephala and S. cordata (basal in some results) occur on the youngest islands. Presumeably, Scalesia pedunculata was already distinct and dispersed on the older islands and founded populations on the new volcanoes that later formed Isabela to originate the two other arboreous species. Species of Scalesia are characterized by nearly allopatric distributions in similar habitats (12 spp. in arid communities, 3 spp. in upland moist communities) within the archipelago. The only synapomorphy correlated with the origin of the upland-habitat lineage is the tree growth habit, though four homoplastic characters also accompany the habitat (loss of leaf adaxial strigosity, moderately sized capitula, glabrous paleae, and corolla tube glabrous). The development of arborescence in a moist habitat under reduced competition is easy to understand (see Itow 1995; Hamann 2001), but further study is needed to determine if the other apomorphies are correlated with reproductive ecology. Eight homoplastic apomorphies but no synapomorphies are correlated with origin of the lineage in the lowland habitat (pubescence strongly strigose, elliptic leaves with entire margins, solitary capitula, blunt phyllaries, paleae deeply divided into elliptic lobes, achenes lacking awns). Unless additional environmental factors, such as humidity, ion content, pollinators, or dispersers, etc. significantly differentiate among both lowland and upland habitats, the species within these two elevational zones appear to occupy nearly the same range of habitats. For example, Scalesia villosa is the only Scalesia species having a dense covering of villous hairs, which presumably functions as a protection from high solar radiation. But several species occupying such habitats are not villous even though villous hairs occur in the related genera. Although S. helleri bears pinnatifid leaves as an autapomorphy, the nearly parapatric and perhaps sister species is distinguished only by two homoplastic apomorphies. Only a single autapomorphy (fully winged petioles) and three homoplastic traits distinguish S. crockeri; nearly parapatric with it is S. aspera, which is differentiated by only four homoplastic traits. Furthermore, diversification among the lowland species has resulted in some sharing apomorphies with some or all of the upland species and vice versa. Scalesia microcephala of mesic forests shares two palea character states (see above) with S. villosa but not with its close congeners in the mesic zone. Thus, demonstrating adaptation of distinguishing features of these species may prove to be challenging. Speciation Patterns.—Because the sister-group to Scalesia remains obscure, comparison of speciation amounts among clades is not possible. It is apparent that this situation will not change until multiple congruent lines of molecular evidence resolve the relationships of the infrageneric groups of Viguiera and other genera in the derived Helianthinae. However, if a DNA sequence in which there is variation among species of Scalesia can be found and analyzed, then, at least speciation rates within Scalesia should be forthcoming. Sampling recommendations.—Given the above situation, it is clear that sampling for future phylogenetic analyses should include, in addition to the present taxa, at least species of Tithonia; Viguiera subg. Amphilepis, sect. Maculatae, and sect. Paradosa; and other segregate genera of the derived Helianthinae. When congruent lines of molecular evidence point to one of these lineages as sister to Scalesia, a complete sampling of species should be attempted to determine whether the whole lineage or a subset of species is the actual sister to Scalesia. CONCLUSION The present study provides a large morphological data set for comparison with molecular phylogenies of Scalesia and close relatives when the molecular data become available. The results confirm that additional taxa and DNA sequences must be sampled to resolve the intergeneric and internal relationships of Scalesia. Furthermore, divergence of Scalesia from its origin to terminal speciations is characterized by combinations of homoplastic apomorphies. Likewise divergence and inter-island geography appear to be poorly correlated. The seeming uniformity within habitat zones, though, appears to be correlated with the homoplasy associated with divergence in Scalesia. Determining the degree to which these homoplastic morphological apomorphies are adaptive should clarify the process of speciation in this and other island endemics. 188 APPENDIX Data matrix. Missing, unknown, or inapplicable=? polymorphic characters indicated by symbols as follows: A={01} B={02} C={03} D={04} E={05} F={12} G={13} H={14} I={15} J={23} K={24} M={35} N={012} P={013} Q={015} R={023} S={024} T={124} U={234} V={0123} X={2345} Y={01234}. Journal of the Botanical Research Institute of Texas 3(1) 1 2 3 4 5 6 Taxa 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 Sc_helleri 0 0 1 0 0 1 0 4 0 0 1 1 0 0 0 1 0 0 1 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 1 2 1 0 2 1 1 A 2 4 N0 3 0 1 1 0 1 2 0 0 1 1 0 0 0 0 0 ? Sc_baurii 0 0 1 0 0 1 0 2 0 0 0 0 0 0 0 1 0 0 1 0 0 2 1 0 0 0 0 0 0 0 0 0 0 0 1 2 1 0 2 1 1 0 2 4 N 0 3 2 1 0 0 1 2 0 0 1 1 0 0 0 0 0 ? Sc_retroflexa 0 0 1 0 0 1 0 A 2 0 1 1 1 0 0 1 0 0 1 0 0 1 1 0 0 0 0 A 0 0 0 0 0 0 1 2 1 0 2 1 A 1 2 4 1 0 3 0 1 1 0 1 2 0 0 1 1 0 0 0 0 0 ? Sc_incisa 0 0 1 0 0 1 0 J 0 0 0 0 0 0 0 1 0 0 1 0 0 2 1 0 0 0 0 0 0 0 0 0 0 0 1 2 1 0 0 1 1 0 2 4 F 0 3 0 1 1 0 1 2 0 0 1 1 0 0 0 0 0 ? Sc_affinis 0 0 1 0 0 1 4 0 F 0 0 0 0 0 0 0 0 2 1 0 0 1 1 0 0 0 0 A 0 0 0 A 0 0 1 1 A 0 N1 A 1 2 C N1 3 0 A 0 0 1 2 0 0 1 1 0 0 F A 0 0 Sc_crockeri 0 2 1 0 0 1 4 0 N 0 1 1 0 0 0 0 0 3 1 0 0 1 1 0 1 0 0 0 0 0 0 0 1 0 1 0 ? ? ? ? 1 1 2 0 0 1 3 2 1 1 0 1 2 0 0 1 1 0 0 F A 0 0 Sc_aspera 0 2 1 0 0 1 4 0 N 0 F F 0 0 0 0 0 1 1 0 0 1 1 0 0 0 0 1 0 0 0 0 0 0 1 0 ? ? ? ? 1 0 2 0 0 0 3 0 1 1 0 1 2 0 0 1 1 0 0 F A 0 0 Sc_divisa 0 2 0 0 0 1 3 A 2 0 1 1 0 0 0 1 0 0 1 0 0 1 1 0 0 0 0 1 0 0 0 0 0 0 1 0 ? ? ? ? 1 1 2 0 0 0 3 2 1 1 0 1 2 0 0 1 1 0 0 F A 0 0 Sc_gordilloi 0 2 1 0 0 1 3 0 A 0 1 1 0 0 0 1 0 0 1 0 0 2 1 1 0 0 0 0 0 0 0 0 0 0 1 0 ? ? ? ? 1 1 2 0 0 0 3 2 1 1 0 1 2 0 0 1 1 0 0 F A 0 0 Sc_atractyloides 0 0 1 0 0 1 5 0 0 0 0 0 0 0 0 0 0 1 A 0 0 1 1 0 3 0 1 0 0 A 0 0 1 A 2 0 ? ? ? ? 0 1 2 0 0 0 3 2 1 1 0 1 2 0 0 1 1 0 0 0 0 0 ? Sc_stewartii 0 0 1 0 0 1 5 0 0 0 1 0 1 0 0 0 0 1 0 0 B 1 1 0 3 0 1 0 0 A 0 0 1 0 1 0 ? ? ? ? 0 1 2 0 0 0 3 2 1 0 0 1 2 0 0 1 1 0 0 0 0 0 ? Sc_villosa 0 1 1 0 0 1 5 0 0 0 0 0 2 0 0 0 0 2 0 0 0 1 1 0 2 0 0 0 0 0 1 0 1 0 1 0 ? ? ? ? 0 1 1 1 0 1 3 0 1 1 0 1 2 0 0 1 1 0 0 0 0 0 ? Sc_cordata 1 0 0 0 0 1 2 0 1 0 0 F B 0 0 0 0 0 1 0 1 3 1 0 A 0 0 0 0 0 0 0 1 0 1 0 ? ? ? ? 1 0 1 1 0 0 3 2 1 0 0 1 2 0 0 1 1 0 0 2 2 A 0 Sc_microcephala 1 0 A 0 0 1 F 0 1 0 0 F A 0 0 0 0 0 1 0 1 3 1 0 A 0 0 0 0 0 0 0 1 0 1 0 ? ? ? ? 0 1 1 1 0 1 3 2 1 0 0 1 2 0 0 1 1 0 0 2 2 0 0 Sc_pedunculata 1 0 1 0 0 1 1 0 A 0 A A 0 0 0 0 0 0 1 0 0 1 1 0 A 0 0 A 0 0 0 0 1 0 1 0 ? ? ? ? 1 0 2 2 N 0 3 2 1 0 0 1 2 0 0 1 F 0 0 2 1 0 0 B_deltoidea A B 1 0 0 1 R 0 2 0 1 0 0 0 0 0 0 0 A 0 1 2 0 1 2 0 0 1 0 0 0 0 1 1 2 1 0 1 0 0 1 1 0 1 0 1 0 1 0 1 0 3 0 0 0 0 F 1 0 2 2 1 0 B_parishii 0 B 1 0 0 1 R 0 2 0 1 1 0 0 0 0 0 0 0 0 0 2 0 1 2 0 0 1 0 0 0 0 1 1 2 1 0 1 0 0 0 0 0 1 0 1 0 1 0 1 0 3 0 0 0 0 1 1 0 2 2 0 0 V_adenophylla 0 B 0 0 0 1 J 0 2 0 1 1 0 0 0 0 0 0 1 0 1 2 0 1 2 0 0 0 0 0 0 0 1 1 1 1 0 0 0 0 1 0 0 G 0 0 2 0 A 1 0 1 0 0 0 1 1 1 0 B C 0 1 V_cordifolia J 2 0 0 1 1 B 0 1 0 1 1 0 0 0 0 0 A 0 0 F 2 0 0 K 0 0 0 1 0 0 1 1 1 1 1 0 0 0 1 1 1 A 1 3 1 0 1 1 1 2 0 0 0 1 1 F 1 0 2 2 1 0 V_grammatogl. 0 1 1 0 1 2 2 0 1 0 0 0 1 0 0 0 0 0 1 1 2 2 1 1 0 0 0 0 F 0 0 1 A A 1 1 0 0 0 1 1 1 A 1 C 1 0 0 1 1 0 0 0 0 1 1 1 1 1 2 2 1 1 V_stenoloba 0 A 1 0 A 1 MD 0 1 0 0 1 0 0 A 0 3 1 0 0 2 0 0 3 0 1 0 1 1 0 0 1 1 F 1 0 0 A 1 2 1 A F C 1 0 2 1 1 2 0 0 0 1 1 0 0 1 0 0 0 ? Si_ghiesbre. 2 A 0 0 1 1 C 0 F 0 0 1 0 0 0 0 0 4 1 1 1 2 0 A 2 0 0 A 2 0 0 1 1 A 0 1 0 0 A 1 0 1 A G 0 1 0 1 1 0 2 1 0 0 1 1 A A F B B A 0 Si_santoros. 2 0 0 0 1 1 0 0 F 0 1 1 0 0 1 0 0 0 0 1 F 2 0 0 2 0 0 1 B 0 0 1 1 0 0 1 0 0 A 1 0 1 A 1 0 1 0 1 1 0 2 A 0 0 1 1 F A 2 2 2 0 0 Si_fruticulosa B A 1 0 1 1 C Y F 0 1 2 0 0 0 0 0 4 A 1 F 2 0 0 2 0 0 1 B 0 0 1 1 0 0 1 0 0 A 1 0 1 A 1 0 1 0 A 1 0 2 A 0 0 1 1 F A 2 B B 0 0 Si_mollinae B 0 1 0 1 1 C Y F 0 0 0 0 0 0 0 0 4 1 1 F 2 0 0 2 0 0 1 0 0 0 1 1 0 0 1 0 A A 1 0 1 A 1 0 1 0 0 1 0 2 A 0 0 1 1 F A 2 2 2 0 0 Si_holwayi B 0 1 0 1 1 C N F 0 0 0 0 0 0 0 0 4 1 1 F 2 0 0 2 0 0 1 G 0 0 1 1 0 0 1 0 0 A 1 0 1 A 1 0 1 0 0 1 0 2 0 0 0 1 1 F A 2 2 2 0 0 Si_steyerm. B B 1 0 1 1 C 0 1 0 0 0 0 0 0 0 0 4 1 1 2 2 0 0 2 0 0 1 B 0 0 1 1 0 0 1 0 0 A 1 0 1 A 1 0 1 2 1 1 0 2 A 0 0 1 1 1 A 2 B B 0 0 Si_annectens B 2 1 0 1 1 C Y F 0 1 1 0 0 0 0 0 Y 1 1 F 2 0 0 2 0 0 A R 0 0 1 1 A 0 1 0 0 A 1 0 1 A 1 0 1 2 1 1 0 2 A 0 0 1 1 F A 2 B B 0 0 Si_tenuis U 0 1 0 1 1 C A 1 0 0 0 0 0 0 0 0 4 A 1 F 2 0 0 2 0 0 1 C 0 0 1 1 0 0 1 0 0 A 1 0 1 A 1 0 1 0 A 1 0 2 A 0 0 1 1 F A 2 0 0 0 ? Si_villasenorii B 2 1 0 1 1 C 0 F 0 1 1 0 0 1 0 0 4 A 1 F 2 0 0 2 0 0 1 C 0 0 1 1 0 0 1 0 0 A 1 0 1 A 1 0 1 2 A 1 0 2 A 0 0 1 1 2 A 2 2 2 A 0 Si_setosa J 0 1 0 1 1 C Y F 0 0 0 0 0 0 0 0 4 1 1 F 2 0 0 2 0 0 1 C 0 0 1 1 0 0 1 0 0 A 1 0 1 A 1 0 1 2 1 1 0 2 A 0 0 1 1 2 A 2 B B 0 0 Si_sanguinea J 2 1 0 1 1 QY F 0 1 A 0 0 0 0 0 V A 1 F 2 0 A 2 0 0 A R 0 0 1 1 A 0 1 0 0 A 1 0 1 A 1 0 1 X A 1 0 2 B 1 0 1 1 F A 2 B B A 0 Si_calva J 2 1 0 1 1 0 Y F 0 1 1 0 0 0 0 0 4 A 1 0 F 0 0 2 0 0 A B 0 0 1 1 A 0 1 0 0 A 1 0 1 A 1 0 1 E A 1 0 2 A 0 0 1 1 F A 2 N B 0 0 Si_lagasciformis 4 B 1 0 1 1 C Y F 0 A A 0 0 0 0 0 4 1 1 F K 0 A 2 0 0 1 C 0 0 1 1 0 0 1 0 0 A 1 0 1 A G 0 1 0 A 1 0 2 2 0 0 1 1 F A 2 B B 0 0 Si_eurylelpis 4 0 0 0 1 1 0 Y F 0 0 0 0 0 0 0 0 4 1 1 F 2 1 0 2 0 0 1 C 0 0 1 1 0 0 0 ? ? ? ? 0 1 A 1 0 1 0 0 1 0 2 0 0 0 1 1 F A 2 B B 0 0 Si_chaseae 4 0 1 0 1 1 C N F 0 0 0 0 0 0 0 0 4 1 1 F 2 1 0 2 0 0 1 0 0 0 1 1 0 0 1 0 0 A 1 0 1 A 1 0 1 2 A 1 0 2 0 0 0 1 1 F A 2 B B 0 0 Blaschke and Sanders, Phylogenetics and speciation of Scalesia 189 Si_dombeyana 4 B 1 0 1 1 C N F 0 1 1 0 0 0 0 0 4 1 1 1 2 1 0 2 0 0 0 0 0 0 1 1 0 0 1 0 0 A 1 0 1 A 1 0 1 2 0 1 0 2 A 0 0 1 1 2 A 2 2 2 A 0 Si_amplexic. 4 2 1 0 1 1 C Y F 0 1 1 0 0 0 0 0 V 1 1 F 2 0 A 2 0 0 0 2 0 0 1 1 1 0 1 0 0 A 1 0 1 A 1 0 1 0 0 1 0 2 2 0 0 1 1 F A 2 B B 0 0 Si_foetida 4 A 1 0 1 1 C Y F 0 A A 0 0 0 0 0 Y 1 1 0 F 0 A 3 0 0 0 0 1 0 1 1 A 0 1 0 0 A 1 0 1 A 1 0 1 B A 1 0 2 A 0 0 1 1 F A 2 2 2 A 0 P_matthewsii 0 1 1 0 0 1 A 0 A 0 F 0 1 0 0 0 0 1 1 0 1 2 A 0 B 0 A A 1 0 A 0 A A 2 1 0 0 A 1 A 0 A 1 A 1 0 0 1 1 0 0 0 0 0 0 A 1 0 2 2 A 1 P_sagasteguii 0 1 1 0 0 1 C 0 2 0 F 0 2 0 0 0 0 0 1 0 1 2 1 0 2 0 0 0 1 0 0 0 1 1 2 1 0 0 0 1 A 0 1 1 1 1 0 0 0 1 0 0 0 0 0 0 A A 0 2 2 A 1 P_ecuadoriensis 0 F 1 0 0 1 P 0 F 0 1 1 1 0 0 0 0 0 1 0 1 2 0 0 2 0 0 0 1 0 0 0 A 0 2 1 0 0 0 1 0 1 A 1 0 1 0 0 0 1 0 0 C 0 0 0 A A 0 2 2 A 1 P_hutchisonii 0 A 1 0 0 2 0 0 A 0 0 0 1 0 0 0 0 1 1 0 1 2 0 0 4 0 0 1 1 0 0 0 0 1 2 1 1 1 0 1 1 1 1 3 A 1 0 1 A 1 0 0 0 0 0 0 1 1 0 2 2 1 1 P_acutifolius 0 N1 0 0 1 I 0 A 0 1 1 0 0 0 0 0 1 A 0 1 F 1 0 2 0 1 1 1 0 0 0 1 1 2 1 0 0 0 1 A 0 0 1 1 1 0 0 1 1 0 0 0 0 0 0 1 1 0 2 2 1 1 P_verbesinoides 0 F 1 0 0 2 1 0 0 0 F 0 2 0 0 0 0 1 0 0 1 2 0 0 B 0 0 0 1 0 0 0 0 0 2 1 0 0 0 1 0 0 0 1 0 1 0 0 1 1 0 0 0 0 0 0 0 0 0 2 2 0 1 P_hypargyreus 0 N 1 A 0 1 R 0 F 0 1 1 0 0 0 0 0 1 1 0 1 1 1 0 1 0 1 1 1 1 1 0 1 1 2 1 0 0 0 1 0 1 0 1 0 1 0 0 0 1 0 A C 0 0 0 1 A 0 2 2 1 1 P_imbaburensis 0 B 1 A 0 1 A 0 N 0 1 1 1 0 0 0 0 1 1 0 1 2 0 0 B 0 0 1 2 0 0 0 0 A 2 1 0 0 0 1 0 0 0 1 0 1 0 0 0 1 0 0 C 0 0 0 A 0 0 2 2 1 1 P_juncosae 0 F 1 0 0 1 0 0 1 0 1 1 1 0 0 0 0 1 A 0 1 1 0 0 0 0 1 1 1 0 1 0 0 A 2 1 0 0 0 1 0 0 0 1 A A 0 0 0 1 0 0 C 0 0 0 2 0 0 2 2 0 1 P_lehmannii 0 1 1 0 0 0 R 0 F 0 1 F 0 0 0 0 0 1 A 0 1 1 1 0 S 0 1 1 F 1 1 0 A A 2 1 0 1 0 0 0 0 0 1 C 1 0 0 0 A 1 1 0 1 0 0 2 0 0 2 2 A 1 P_nigrescens 0 F 1 1 0 1 C 0 F 0 1 F A 0 0 0 0 0 1 0 1 1 1 2 S 0 0 1 2 0 0 0 0 A 2 1 0 F 0 0 0 0 0 1 C 1 0 0 1 1 1 1 0 1 0 0 1 0 0 2 2 1 1 P_andinus 0 A 1 0 0 2 0 0 1 0 0 0 2 0 0 0 0 0 0 0 B 1 1 0 S 0 1 1 2 0 0 0 0 A 2 1 0 1 0 0 A 0 0 1 0 1 0 0 0 1 1 1 0 0 0 0 1 0 0 2 2 0 1 P_storkhorton. 0 F 1 1 0 1 0 0 1 0 1 F 0 0 0 0 0 0 1 0 1 1 1 0 S 0 1 1 2 0 0 0 1 1 2 1 ? 1 0 0 0 A 0 1 C 1 0 0 0 1 1 1 0 0 0 0 1 0 0 2 2 0 1 P_acuminatus 0 F 1 0 1 1 C 0 0 0 F 0 F 0 0 0 0 0 1 1 1 1 1 0 E 0 0 1 2 0 0 0 0 0 2 1 0 1 0 0 A 0 0 1 0 1 0 0 1 1 1 1 1 0 0 0 1 0 0 2 2 0 1 P_cinerascens 0 F 1 0 1 1 A 0 1 0 1 1 1 0 0 0 0 0 1 A 1 1 1 0 B 0 0 1 2 A 0 0 1 1 2 1 1 F 0 0 0 0 0 1 C 1 0 A A 1 1 1 1 0 0 0 1 0 0 2 J 0 1 P_mollicomus 0 F 1 0 A 1 H 0 1 0 1 0 F 0 0 0 0 1 1 1 A 1 1 0 S 0 0 1 2 0 1 0 0 A 2 1 1 1 0 0 0 0 0 1 C 1 0 0 0 1 1 1 0 0 0 0 1 0 0 2 3 0 1 P_macranthus 0 F 1 0 A 1 A 0 2 0 1 A 0 0 0 0 0 0 1 1 1 1 1 2 2 0 1 0 2 1 0 0 1 1 2 1 0 F 0 1 A 0 0 F C A 0 0 0 1 1 1 0 0 0 0 1 0 0 2 3 0 1 P_sanchezii 1 F 1 0 1 0 0 0 1 0 1 0 1 0 0 0 0 0 1 A A 0 1 0 2 0 1 0 1 1 0 0 1 1 2 1 0 1 0 0 2 0 0 2 C A 0 0 1 0 1 1 0 0 0 0 1 0 0 2 2 0 1 P_youngiorum 0 N 1 0 1 1 0 0 A 0 1 1 0 0 0 0 0 0 A A 1 0 1 0 2 0 1 1 1 1 0 0 1 1 2 1 0 F 0 0 1 1 0 F 0 A 0 0 0 1 1 1 1 0 0 0 1 0 0 2 2 0 1 P_schillingii 0 N1 0 1 0 C 0 F 0 1 0 2 0 0 0 0 0 A 0 1 1 1 0 2 A 1 1 1 1 0 0 1 1 2 1 0 A 0 0 A 0 0 F C A 0 0 0 1 1 1 C 0 0 0 1 0 0 2 2 0 1 P_amoenus 0 A 1 0 1 1 P 0 N 0 0 0 F 0 0 0 0 A A 1 A 0 1 0 0 A 0 1 1 0 0 0 0 1 2 1 1 0 0 0 1 A 0 F C A 0 0 1 1 1 1 0 0 0 0 A 1 0 2 2 A 1 P_robinsonii 0 1 1 A A 1 A 0 1 0 1 0 2 0 0 0 0 1 1 1 1 0 1 2 0 1 1 1 1 A A 0 0 A 2 1 1 1 0 0 1 0 0 1 0 1 0 1 1 1 1 1 1 0 0 0 1 A 0 2 2 A 1 P_steubelii 1 F 1 A 0 0 A 0 A 1 1 0 2 0 1 0 0 0 1 0 0 0 1 2 2 0 1 0 ? 0 1 0 1 0 2 1 0 F 0 0 0 0 0 1 0 1 0 0 0 1 1 1 1 0 0 0 1 0 0 2 2 0 1 P_smithii 0 1 1 0 0 0 A 0 0 1 1 0 2 0 1 0 0 0 A 0 B 1 1 2 2 0 1 1 2 1 1 0 1 1 2 1 0 1 0 0 0 0 0 F C A 0 0 A 1 1 1 1 0 0 0 1 0 0 2 2 0 1 P_jelskii 0 N1 A 1 0 A 0 0 1 A A 2 0 1 0 0 0 A 1 F 0 1 2 2 0 1 1 2 1 A 0 1 1 2 1 0 0 0 0 0 0 0 F C A 0 0 A 1 1 1 C 0 0 0 1 0 0 2 2 0 1 P_lodicatus 0 F 1 1 0 0 0 0 0 1 1 0 2 0 1 0 0 1 1 0 A 1 1 0 B 0 0 1 2 0 0 0 0 0 2 1 0 1 0 0 A 0 0 1 0 1 0 0 0 1 1 1 C 0 0 0 A 0 0 2 2 0 1 P_microphyllus 0 F 1 0 0 0 Q 0 0 1 1 0 2 0 1 A 0 1 0 0 0 2 0 0 R 0 0 A 1 0 0 0 0 0 2 1 0 0 0 0 A 0 0 1 0 1 0 0 0 1 1 1 A 0 0 0 1 A 0 2 2 A 1 P_subniveus 0 F 1 0 A 0 I 0 0 1 F 0 2 0 1 0 0 0 0 0 0 1 0 0 R 0 1 1 ? 0 1 0 1 A 2 1 0 A 0 0 0 0 0 1 C 1 0 1 0 1 1 1 0 0 0 0 1 0 0 2 2 0 1 P_cajamarcensis 0 1 1 0 0 0 1 0 0 1 0 0 2 1 1 0 0 0 0 0 A 1 A 0 B 0 1 1 ? 0 1 0 1 A 2 1 0 1 0 0 0 0 0 1 C 1 0 0 0 A 1 1 1 0 0 0 1 0 0 2 2 0 1 P_discolor 0 F 1 0 A 1 5 0 0 1 1 0 2 A 1 A 1 0 0 A 0 2 A 0 2 0 0 1 2 0 A 0 1 0 2 1 0 0 0 0 1 0 0 1 0 1 0 1 0 A 1 1 1 0 0 0 1 0 0 2 2 0 1 P_decumbens 0 2 1 0 0 0 5 0 0 1 1 0 2 1 1 1 0 2 0 0 0 2 A 0 2 0 0 0 2 0 0 0 1 A 2 1 0 0 0 0 1 0 0 1 C 1 0 1 0 A 1 1 0 0 0 0 1 0 0 2 3 0 1 P_woodsonianus 0 2 1 0 1 0 4 0 0 1 1 0 2 0 1 0 0 0 0 1 B 1 1 0 0 0 0 1 2 0 0 0 0 0 2 1 0 0 0 0 1 0 0 1 C 1 0 0 0 A 1 1 0 0 0 0 1 0 0 2 3 0 1 P_davidii 0 F 1 0 0 0 1 0 1 1 1 1 0 0 1 0 0 0 0 0 A 1 1 0 2 0 0 1 2 0 0 0 1 A 2 1 0 A 0 1 1 0 0 1 0 1 0 0 0 1 1 1 1 0 0 0 1 0 0 2 2 0 1 P_lanatus 0 F 1 0 1 0 A 0 0 1 1 0 2 0 1 0 0 0 0 0 1 1 A 0 T 0 0 1 2 0 0 0 0 A 2 1 0 1 0 0 A 1 0 1 0 1 0 0 0 A 1 1 1 0 0 0 1 0 0 2 2 0 1 P_argenteus 0 F 1 0 A 0 1 0 A 1 1 0 F 0 1 0 0 1 0 0 0 2 1 0 0 0 0 1 2 0 0 0 0 1 2 1 0 1 0 0 1 1 0 1 0 1 0 0 0 0 1 1 0 0 0 0 F 0 0 2 2 A 1 P_viridior 0 F 1 0 0 0 1 0 A 1 1 0 F 0 1 0 0 1 0 0 0 1 A 0 S 0 1 1 0 0 0 0 A 1 2 1 A A 0 0 0 0 0 1 0 1 0 1 0 0 1 1 C 0 0 0 1 0 0 2 2 0 1 P_senex 0 F 1 0 1 2 0 0 A 1 1 0 2 0 1 0 0 0 1 0 1 2 0 0 0 0 0 0 0 0 0 0 0 0 2 1 0 0 0 0 1 1 0 1 0 1 0 0 0 A 1 1 1 0 0 0 1 0 0 2 2 0 1 H_annuus 4 B 1 0 0 1 B 0 F 0 1 1 0 0 0 0 0 A 1 0 0 A 1 B 1 0 1 0 0 1 0 1 1 1 1 1 0 F 0 1 2 1 1 3 0 1 0 0 1 1 2 3 A 0 1 1 2 1 0 2 2 A 1 H_tuberosus 3 B 1 0 1 1 1 0 1 0 1 1 0 0 0 0 0 2 1 0 1 1 1 1 1 0 1 0 2 1 0 1 1 1 1 1 0 F 0 1 2 1 1 1 0 1 0 1 0 1 0 3 0 0 1 1 2 A 0 2 2 A 1 190 Journal of the Botanical Research Institute of Texas 3(1) ACKNOWLEDGEMENTS We thank Todd Wood for encouragement and comments and Stephanie Mace for assistance with graphics. 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