Taxonomy of Tropical West African Bivalves II. Psammobiidae
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Bull. Mus. natn. Hist. nat., Paris, 4' sér., 11, 1989, section A, n° 4 : 693-731. Taxonomy of tropical West African bivalves II. Psammobiidae by Rudo VON COSEL Abstrait. — Of the eleven known Eastern Atlantic species of the bivalve family Psammobiidae, Ave are members of the European fauna and are also found in more or less long ranges on the coast of tropical West Africa. Four species are restricted to the West African tropical zone, one is exclusively European and one is only known from a small coastal strip of Northern Angola, and from Côte d'Ivoire. Gari jousseaumeana Bertin, 1880, G. depressa (Pennant, 1777), G. costulata (Turton, 1810) seem to have a disjunct distribution with a probable distribution gap within the tropical zone. Three species are new : Gari pseudoweinkauffi n. sp. from infralittoral sandy bottom, hitherto misidentified with the Red Sea species G. weinkauffi (Crosse, 1864), G. gofasi n. sp. from infralittoral sandy bottom of the West African tropical zone, and Sanguinolaria africana n. sp. also from tropical West Africa and hitherto confounded with the Caribbean S. sanguinolenta (Gmelin, 1791). Résumé. — Onze espèces de la famille Psammobiidae sont connues de l'Atlantique oriental dont cinq en Europe et dans une partie au moins de l'Afrique Occidentale tropicale. Quatre espèces sont exclusivement tropicales, une espèce est restreinte à l'Europe et une espèce n'est connue que d'une petite partie de la côte du nord de l'Angola et de Côte d'Ivoire. Gari jousseaumeana Bertin, 1880, G. depressa (Pennant, 1777) et G. costulata (Turton, 1810) ont très probablement une distribution disjointe avec une interruption dans une partie plus ou moins grande de la zone tropicale. Trois espèces sont nouvelles : G. pseudoweinkauffi n. sp. des fonds sableux infralittoraux jusqu'ici confondu avec l'espèce de mer Rouge G. weinkauffi (Crosse, 1864), G. gofasi n. sp. des fonds sableux infralittoraux de la zone tropicale ouest- africaine et Sanguinolaria africana n. sp., de même répartition, jusqu'ici confondu avec l'espèce caraïbe S. sanguinolenta (Gmelin, 1791). R. VON COSEL, Marine biologist at ORSTOM, Laboratoire de Biologie des Invertébrés marins et Malacologie, Muséum national d'Histoire naturelle, 55, rue Buffon, F-75005 Paris. Of the Psammobiidae, a family of sand-dwelling tellinacean bivalves, eleven species are now known from the Eastern Atlantic, and ten of them are présent in tropical West Africa. Seven West African species are named, but some are still poorly known ; the remaining three will be described here. The only non-West African species, G. tellinella (Lamarck, 1818) is included here to give a complète survey of the Eastern Atlantic species. Nine species belong to the genus Gari Schumacher, 1817, one to Heterodonax Môrch, 1853, and one to Sanguinolaria Lamarck, 1799. This genus was often treated in an own family Sanguinolariidae, but KEEN in MOORE (1969) included this as a subfamily in the Psammobiidae. As a generic revision can be carried out only on a Worldwide level, no attempt has been made here, and a conservative, noncritical systematic has been employed. — 694 — Gari fervensis (Gmelin, 1791) Tellina angulata Born, 1780 : 30, pl. 2; fig. 5 (non Linné, 1758). Tellina fervensis Gmelin, 1791 : 3235 (name on the Officiai List of Spécifie Names (ICZN,Opinion 910, 5. june, 1970). Tellina bornii Gmelin, 1791 : 3231. TYPE MATERIAL : Not localized (not in ZMC, SCHIOTTE, in litt., 10.11.90). TYPE LOCALITY : " Oceano septentrionali ". DESCRIPTION Shell medium-sized, up to 53 mm long, moderately solid, variable in outline, slightly inequivalve, nearly equilateral, elongate, length/width ratio ranging between 1.9 and 2.4 : 1. Valves compressed, left valve considerably to very slightly more convex than right valve, posterior end somewhat twisted to the right side and occasionally slightly gaping. Anterior margin rounded, posterior margin obliquely truncated, with sharp angles. Postero-dorsal margin straight or slightly convex, with a weak slope only, ending abruptly in the angle to the posterior truncation. Ventral margin gently convex, posteriorly bent upwards, postero-ventral margin weakly concave, ending in the sharp angle to the posterior truncation. Beaks just before the vertical midline. Exterior with numerous, fine, concentric ridges, occasionally becoming obsolète on the left valve. Sharp keel running from the umbos to the postero-ventral angle and delimiting the postero-dorsal part with about eight radial ribs crossing the concentric sculpture and giving this part of the valves a cancellate pattern. Hinge plate narrow, two bifid cardinals in the right valve, the posterior strongly bifid, left valve with one stronger vertical bifid cardinal and one narrow oblique-subhorizontal posterior cardinal ; no laterals. Palliai sinus rounded, extending just to the level of the beaks, its ventral limb confluent with the palliai line for two thirds of its length. Outside of valves whitish to pale violet with light to darker brownish or reddish to violet radial rays, often with lighter mottlings on them. Occasionally, only irregular mottlings are présent instead of rays, with growth stages marked by darker concentric zones. Periostracum rather strong, brown to olive, normally peeling off on earlier parts of the valves. On West African spécimens, periostracum very thin and transparent. Inside light to dark violet, in some spécimens light brownish to yellowish, often bright yellow in Mauritanian spécimens. Selected measurements with length/width ratio 53.7 x 24.0 mm North Sea (55°20' N/05°00' E) 2.2 51.0 x 24.3 mm Roscoff, Atlantic France 2.1 50.8 x 25.8 mm North Sea (55°35' N/04°24' E) 2.0 50.6 x 25.2 mm Crozon, Atlantic France 2.0 49.6 x 24.0 mm Saltcoats, Scotland 2.1 46.5 x 23.1 mm Gullane, Scotland 2.0 45.0 x 22.1mm Laredo, Atlantic Spain 2.0 45.0 x 20.5 mm Quiberon, Atlantic France 2.2 42.0 x 19.7 mm La Franqui, Mediterranean France 2.1 — 695 — 40.4 X 20.3 mm Douarnenez, Atlantic France 2.0 39.6 X 18.1 mm Gullane 2.2 . 38.0 X 17.4 mm La Franqui 2.2 : 33.6 X 16.5 mm Guinea (10°27'N/15°43,5'W) 2.0 32.4 X 15.7mm Brest, Atlantic France 2.1 32.3 X 16.9 mm B. de l'Étoile, Mauritania 1.9 : 31.2 X 14.6 mm Guinea (10°27'N/15°43,5'W) 2.1 31.0 X 14.3 mm Sète, Mediterranean France 2.2 : 30.8 X 15.3 mm B. Cansado, Mauritania 2.0 • 29.0 X 13.7 mm Guinea (9°55,5'N/14°27'W) 2.1 28.9 X 13.5 mm Guinea (10°27'N/15°43,5'W) 2.1 • 28.0 X 12.1 mm Ceuta, Strait of Gibraltar 2.3 : 26.5 X 13.8 mm Guinea (10W N/14°24"W) 1.9 . 26.5 X 11.1 mm Ilha de Luanda, Angola 2.4 : 25.0 X 11.1 mm Baia de Sagres, Portugal 2.3 : 24.7 X 12.3 mm Guinea (9°50'N/14°14'W) 2.0 : 24.7 X 11.8 mm Guinea (9°42'N/13°56'W) 2.1 : 24.6 X 12.0 mm Pointe-Noire, Congo 2.1 : 23.8 X 11.7 mm Guinea (9°12,3'N/13°37'W) 2.0 : 23.7 X 11.8 mm Abidjan, Côte d'Ivoire 2.0 : 23.7 X 11.6 mm Guinea (9°50'N/14°14'W) 2.0 : 23.7 X 10.8mm Guinea (9°55'N/14°27'W) 2.2 : 23.3 X 11.0 mm Alger, Algeria 2.1 : 23.2 X 10.7 mm Guinea (9°30'N/14°02'W) 2.2 : 22.4 X 11.8 mm Guinea (9°18'N/13°38'W) 2.0 : 21.7 X 11.0 mm Guinea (9° 12,3'N/13°37'W) 2.0 : 21.3 X 10.5 mm Côte d'Ivoire (5°04'N/5°18'W) 1.9 : 20.0 X 9.5 mm Cacuaco, Angola 2.1 : DISTRIBUTION : Iceland (valves only, MADSEN, 1949); Faroe, Norway (70° N, H0IS^TER, 1986) and British Isles southward to Angola (Lucira); throughout the Mediterranean. MATERIAL EXAMINED : North Sea : 55°20' N/05°00' E, 1 sh. ; 55°35' N/4°24' E, 2 sh., both leg. TÛRKAY, SMF. Great Britain : West coast of Scotland, Saltcoats, Firth of Clyde, beach, 2 v. ; East coast of Scotland, Aberlady Bay and Gullane Bay, Firth of Forth, beach, several v., ail leg. B. & R. VON COSEL, X.1987, MNHN ; Weymouth, 2 sh., SMF ; Paignton, 1 v., leg. VON COSEL, X.1960, SMF ex author's coll. ; Teignmouth, 1 sh., coll. STAADT, MNHN. Atlantic France : Celtic Sea, 49°09,1 ' N/08° 10,4' W, 132 m, 1 v. ; 48°39,1'N/08°37,3'W, 164m, 1 v., both dredged R/V "Thalassa", XII. 1983, leg. VON COSEL, MNHN; Roscoff, Finistère, 3 sh., old coll. MNHN; Brest, Finistère, 2 sh., coll. LOCARD, 1892; Crozon, Finistère, 2 sh., 2 v., old coll. MNHN; Douarnenez, Finistère, 5 v., coll. SOYER ex GUIDEAU, MNHN; Concarneau, Finistère, 3 v., coll. LOCARD, 1892; Quiberon, Morbihan, Plage de Conguel, on beach, 1 sh., 1 v., leg. B. & R. VON COSEL, 28.III. 1987; Le Pouliguen, Loire-Atlantique, 1 sh. ; Le Croisic, Loire-Atlantique, 1 sh., both coll. H. FISCHER, ail MNHN. Atlantic Spain : Laredo, Prov. Santander, on beach, 3 sh., 3 v., leg. VON COSEL & GOFAS, 7.II. 1988. Algeciras, 2 sh., leg. RÛPPELL, SMF; Ceuta, Strait of Gibraltar, Ensenada de la Almadraba, 20-45 m, numerous v., leg.