Ostracod evidence for the Neolithic environment of Rio Sizandro, Portugal: Part 2

Abstract

The environmental background to the Neolithic occupation of the Rio Sizandro, western Portugal is elucidated via the ostracod assemblages and sedimentology of a well-dated part of borehole COU_14 from near the village of Coutada. Results from this location, under greater marine influence than sites previously studied, confirm changes from fluvial to brackish estuarine and lagoonal conditions driven by the interaction of changing eustatic sea level, barrier lagoon formation and valley infill from erosion related to climate change and possible human activity.

Appendices

Appendix 1

List of ostracod taxa found in Borehole COU_14, Coutada, Rio Sizandro.

The species of the genera Neonesidea, Paradoxostoma, Sclerochilus and Xestoleberis, all of them generally uncommon, were rarely identified due to their scarcity and dimensions (juveniles) and were considered together as spp. for the counts (Fig. 5). Aurila convexa and Aurila woutersi were identified when present as adults, as most of the specimens were juveniles they were counted together (Fig. 5). Identifications were mainly based on Athersuch et al. (1989), Bonaduce et al. (1976), Meisch (2000) and Cabral and Loureiro (2013). Systematics according to Horne et al. (2002).

Class Ostracoda Latreille, 1802

Subclass Podocopa Sars, 1866

Order Podocopida Sars, 1866

Suborder Cytherocopina Gründel, 1967

Superfamily Cytheroidea Baird, 1850

Family Bythocytheridae Sars, 1866

Genus Bythocythere Sars, 1866

 Bythocythere bradyi Sars, 1926 - Fig. 6a

Genus Pseudocythere Sars, 1866

 Pseudocythere caudata Sars, 1866

Genus Sclerochilus Sars, 1866

 Sclerochilus spp. - Fig. 6b

Family Cuneocytheridae Mandelstam, 1959

Genus Cuneocythere Lienenklaus, 1894

 Cuneocythere semipunctata (Brady, 1868)

Family Cushmanideidae Puri, 1974

Genus Pontocythere Dubowsky, 1939

 Pontocythere elongata (Brady, 1868) - Fig. 6c

Family Cytherideidae Sars, 1925

Genus Cyprideis Jones, 1857

 Cyprideis torosa (Jones, 1850) - Fig. 6d–e

Family Cytheruridae G. W. Müller, 1894

Genus Cytheropteron Sars, 1866

 Cytheropteron dorsocostatum Whatley and Masson, 1980 - Fig. 7b

Genus Hemicytherura Elofson, 1941

 Hemicytherura aff. defiorei Ruggieri, 1953 - Fig. 6f

Genus Microcytherura G. W. Müller, 1894

 Microcytherura fulva (Brady and Robertson, 1874) - Fig. 6g

Genus Pseudocytherura Dubowsky, 1939

 Pseudocytherura cf. calcarata (Seguenza, 1880) - Fig. 6h

Genus Semicytherura Wagner, 1957

 Semicytherura acuminata (G.W.Müller, 1894) - Fig. 6i

Semicytherura acuta (G.W.Müller, 1912) - Fig. 6j–k

Semicytherura acuticostata ventricosa (Sars, 1866) - Fig. 6l

Semicytherura arcachonensis Yassini, 1969 - Fig. 6m

Semicytherura robertsi Whittaker and Horne, 2009 - Fig. 6n–o

Semicytherura sella (Sars, 1866) - Fig. 5p

Semicytherura cf. stilifera Bonaduce, Ciampo and Masoli, 1976 - Fig. 6q

 Semicytherura sulcata (G. W. Müller, 1894) - Figs. 6r and 7a

Genus Tetracytherura Ruggieri, 1952

 Tetracytherura angulosa (Seguenza, 1880)

Family Eucytheridae Puri, 1954

Genus Eucythere Brady, 1868

 Eucythere prava Brady and Robertson, 1869 - Fig. 7c

Family Hemicytheridae Puri, 1953

Genus Aurila Pokorny, 1955

 Aurila arborescens (Brady, 1865)

 Aurila convexa (Baird, 1850) - Fig. 7d

 Aurila woutersi Horne, 1986 - Fig. 7e

Genus Caudites Coryell and Fields, 1937

 Caudites calceolatus (O. G. Costa, 1853) - Fig. 7f

Genus Hemicythere Sars, 1925

 Hemicythere rubida (Brady, 1868)

Genus Heterocythereis Elofson, 1941

 Heterocythereis albomaculata (Baird, 1838) - Fig. 7g–i

Genus Urocythereis Ruggieri, 1950

 Urocythereis britannica Athersuch, 1977 - Fig. 7k

Family Leptocytheridae Hanai, 1957

Genus Callistocythere Ruggieri, 1953

 Callistocythere badia (Norman, 1862) - Fig. 7l

  Callistocythere curryi Horne, Lord, Robinson and Whittaker, 1990 - Fig. 7m

 Callistocythere littoralis (G. W. Müller, 1894)

 Callistocythere murrayi Whittaker, 1978 - Fig. 7n

Genus Leptocythere Sars, 1928

 Leptocythere castanea (Sars, 1866) - Fig. 7o

 Leptocythere cribrosa (Brady, Crosskey and Robertson, 1874)

 Leptocythere lacertosa (Hirschmann, 1912)

 Leptocythere macallana (Brady and Robertson, 1869)

 Leptocythere fabaeformis (G. W. Müller, 1894) - Fig. 7p–r

 Leptocythere pellucida (Baird, 1850) - Fig. 8a–b

 Leptocythere porcellanea (Brady, 1869) - Fig. 8c

Family Limnocytheridae Klie, 1938

Limnocythere s. str. Brady, 1867

 Limnocythere inopinata (Baird, 1845) - Fig. 8r

Family Loxoconchidae Sars, 1925

Genus Elofsonia Wagner, 1957

 Elofsonia pusilla (Brady and Robertson, 1870)

Genus Loxoconcha Sars, 1866

 Loxoconcha elliptica Brady, 1868 - Fig. 8d

 Loxoconcha malcomsoni Horne and Robinson, 1985

 Loxoconcha rhomboidea (Fischer, 1855) - Fig. 8e

Genus Palmoconcha Swain and Gilby, 1974

 Palmoconcha laevata (Norman, 1865)

Genus Roundstonia Neale, 1973

 Roundstonia robertsoni (Brady, 1868)

Genus Sagmatocythere Athersuch, 1976

 Sagmatocythere napoliana (Puri, 1963) - Fig. 8f

Family Neocytherideidae Puri, 1957

Genus Neocytherideis Puri, 1957

 Neocytherideis subulata (Brady, 1868) - Fig. 8g

Genus Procytherideis Ruggieri, 1978

  Procytherideis aff. subspiralis (Brady, Crosskey and Robertson, 1874)

Genus Sahnicythere Athersuch, 1982

 Sahnicythere retroflexa (Klie, 1936)

Family Paracytherideidae Puri, 1957

Genus Paracytheridea G. W. Müller, 1894

 Paracytheridea sp.

Family Paradoxostomatidae Brady and Norman, 1889

Genus Cytherois G. W. Müller, 1884

 Cytherois fischeri (Sars, 1866) - Fig. 8h

Genus Paradoxostoma Fischer, 1855

 Paradoxostoma spp.

Family Thaerocytheridae Hazel, 1967

Genus Thaerocythere Hazel, 1967

 Thaerocythere hoptonensis (Brady, Crosskey and Robertson, 1874) - Fig. 7j

Family Trachyleberididae Sylvester-Bradley, 1948

Genus Basslerites, Teichert, 1937

 Basslerites teres (Brady, 1869) - Fig. 8i

Genus Carinocythereis Ruggieri, 1956

 Carinocythereis whitei (Baird, 1850)

Genus Costa Neviani, 1928

 Costa runcinata (Baird, 1850)

Genus Hiltermannicythere Bassiouni, 1970

 Hiltermannicythere emaciata (Brady, 1867)

Family Xestoleberididae Sars, 1928

Genus Xestoleberis Sars, 1866

 Xestoleberis rubens Whittaker, 1978 - Fig. 8j

 Xestoleberis spp.

Suborder Bairdiocopina Gründel, 1967

Superfamily Bairdioidea Sars, 1888

Family Bairdiidae Sars, 1888

Genus Bairdia McCoy, 1844

 ‘Bairdia’ subcircinata (Brady and Norman, 1869) - Fig. 8k

Genus Neonesidea Maddocks, 1969

 Neonesidea sp. 2 (Bonaduce, Ciampo and Masoli, 1976) - Fig. 8l

 Neonesidea spp.

Suborder Cypridocopina Gründel, 1967

Superfamily Cypridoidea Baird, 1845

Family Cyprididae Baird, 1845

Genus Cypridopsis Brady, 1867

 Cypridopsis vidua (O.F. Müller, 1776) - Fig. 8m

Genus Sarscypridopsis McKenzie, 1977

 Sarscypridopsis aculeata (Costa, 1847)

Family Ilyocyprididae Kaufmann, 1900

Genus Ilyocypris Brady and Norman, 1889

 Ilyocypris bradyi Sars, 1890 - Fig. 8n–o

 Ilyocypris inermis Kaufmann, 1900 - Fig. 8p–q

Appendix 2

Main ecological groups of the ostracod species collected in Borehole COU_14, Coutada, Rio Sizandro, with remarks on environmental significance of the most important species. Ecological characteristics especially based on Athersuch et al. (1989), Bonaduce et al. (1976) and Cabral and Loureiro (2013).

Group 1: brackish water species.

Cyprideis torosa (Jones, 1850) - a widespread species (Europe, Asia, Africa), highly euryhaline, found from inland lakes to marginal marine settings; prefers a muddy or sandy mud substrate, also found on algae (Athersuch et al. 1989). In Portugal found alive from the tidal flat to the low marsh in estuaries and lagoons (Cabral and Loureiro 2013).

Loxoconcha elliptica Brady, 1868 - a very common species found from NW Europe to the Mediterranean, usually associated with algae and mud, in estuaries, lagoons and pools (Athersuch et al. 1989). In Portugal, highly euryhaline, found alive from the tidal flat to the high marsh in estuaries and lagoons (Cabral and Loureiro 2013).

Cytherois fischeri (Sars, 1866) - a common highly euryhaline species, found from the Mediterranean to western Europe, usually associated with sand and algae, often found close to river mouths (Athersuch et al. 1989). In Portugal found alive especially on muddy substrates, in marshes of several estuaries, from the tidal flat to the lower part of the low marsh (Cabral and Loureiro, 2013).

Leptocythere porcellanea (Brady, 1869) - a western European species, usually found in mud substrates in sheltered creeks (Athersuch et al. 1989). In Portugal, highly euryhaline, found alive especially on muddy substrates, in marshes of several estuaries, from the tidal flat to the lower part of the high marsh (Cabral and Loureiro 2013).

Leptocythere lacertosa (Hirschmann, 1912) - an estuarine western European species, usually found on mud or fine sand (Athersuch et al. 1989). In Portugal found alive on muddy and sandy muddy substrates, in marshes of several estuaries, from the tidal flat to the lower part of the high marsh (Cabral and Loureiro 2013).

Callistocythere murrayi Whittaker, 1978 - a western European species, usually associated with algae (Athersuch et al. 1989), found alive in Portugal on muddy and sandy mud substrates, in marshes of several estuaries, from the tidal flat to the low marsh (Cabral and Loureiro 2013).

Loxoconcha malcomsoni Horne and Robinson, 1985 - a rare species, until now only known living in outer estuaries of British Isles and mainland Portugal (probable record in Azores – Meireles et al. 2014), in mud and mud-sand substrates, in salt marshes, close to the low marsh (Horne and Boomer 2000; Loureiro et al. 2009; Cabral and Loureiro 2013).

Group 2: marine littoral to sublittoral species, prefering sandy to silty sandy or muddy substrates, frequently with algae (phytal forms).

Loxoconcha rhomboidea (Fischer, 1855) - a phytal marine species, living in western Europe and Mediterranean, generally on littoral and shallow sublittoral zones, also found in outer estuaries (Athersuch et al. 1989; Athersuch and Whittaker 1976). In Portugal, found alive from the low to the high marsh in rare estuaries (Cabral and Loureiro 2013).

Heterocythereis albomaculata (Baird, 1838) - a phytal, littoral and sublittoral marine species, often abundant in rock pools, living in western Europe and Mediterranean (Athersuch et al. 1989). In Portugal found alive associated with green algae and sediment, in outer estuaries and intertidal rock pools and therefore having some tolerance of salinity variation (Cabral and Loureiro 2013).

Leptocythere fabaeformis (G.W. Müller, 1894) - a phytal/littoral marine species, euryhaline, tolerating a very wide salinity range, 13 to 33 (Yassini 1969), known from the Mediterranean to western Europe, until France. In Portugal found alive on mud substrates in the tidal flat of only one estuary (Cabral and Loureiro 2013).

Aurila convexa (Baird, 1850) - known from the Mediterranean to western Europe, until France/southern Britain, is a common species, living amongst algae, algal debris or on sand, silty sand and silt at different depths in continental shelf (up to 122 m in the Mediterranean) and in littoral zones (Athersuch et al. 1989; Bonaduce et al. 1976). In Portugal, until now, not found alive, but empty valves and carapaces are frequently abundant in Holocene and Recent marginal marine settings and in Recent littoral to sublittoral (until the continental slope) sediments (Cabral and Loureiro 2013).

Aurila woutersi Horne, 1986 – a phytal, littoral and shallow sublittoral species, living in western Europe (surely found in Great Britain - Athersuch et al., 1989). In Portugal, until now, never found alive but empty valves and carapaces were found in Holocene and Recent marginal marine sediments (Cabral and Loureiro 2013).

Aurila arborescens (Brady, 1865) - known from the Mediterranean, as Aurila woodwardi (Brady, 1868) to western Europe, until southern Britain, it is a littoral? to sublittoral marine species living in the Mediterranean at depths not exceeding 20 m (Athersuch et al. 1989; Bonaduce et al. 1976). In Portugal, until now, not found alive, but carapaces and empty valves were found in Holocene marginal marine sediments (Cearreta et al. 2003; Cabral et al. 2006; Cabral et al. 2011a; Cabral and Loureiro 2013).

Pontocythere elongata (Brady, 1868) - a western European species generally living on sand substrates, in marine and outer estuarine conditions (Athersuch et al. 1989). In Portugal, until now, not found alive, but empty valves and carapaces are frequent in marginal marine Holocene and Recent sediments (Cabral and Loureiro 2013).

Urocythereis britannica Athersuch, 1977 - a western European species generally living on sand substrates, in marine littoral and shallow sublittoral conditions (Athersuch et al. 1989). In Portugal, until now, not found alive, but empty valves and carapaces are frequent in Holocene and Recent marginal marine settings and in Recent littoral to sublittoral (until the continental slope) sediments (Cabral and Loureiro 2013).

Thaerocythere hoptonensis (Brady, Crosskey and Robertson, 1874) - a western European species, with records in Recent sediments from the United Kingdom, Spain, northern Morocco (continental shelf) and Portugal (Wood and Whatley 1997). In Portugal, until now, not found alive, but empty valves and carapaces are frequent in marginal marine Holocene and Recent sediments and in the western Algarve continental shelf, until 104 m depth (Cabral et al. 2011b; Cabral and Loureiro 2013).