taxonID	type	description	language	source
666D24433E50FFAC041DFDE0B5E9C8F7.taxon	materials_examined	TYPE SPECIES. — Phacoides (Lucinoma) gaini Lamy, 1920. SPECIES INCLUDED. — Lamylucina gaini (Lamy, 1920) n. comb.; Lamylucina exgaini n. sp.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E50FFAC041DFDE0B5E9C8F7.taxon	etymology	ETYMOLOGY. — In memory of Édouard Lamy, who was the first “ modern ” revisor of Lucinidae and who described the type species of this genus.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E50FFAC041DFDE0B5E9C8F7.taxon	distribution	DISTRIBUTION. — Tropical West Africa.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E50FFAC041DFDE0B5E9C8F7.taxon	diagnosis	DIAGNOSIS. — Shells small, up to 20 mm, subcircular to circular, very compressed. Beaks small, almost median or slightly in front of the vertical midline. Surface with fine, more or less widely spaced to contiguous commarginal ridges or lamellae, some of them becoming more or less lamellate on the antero- and postero-dorsal margin. Posterior area delimited by a shallow radial depression. Lunule very short and broad, escutcheon very long and narrow. Inner margin smooth. Hinge with one small cardinal tooth in the right valve and two in the left valve, often very weak to almost obsolete. No lateral teeth. Ventral prolongation of the anterior adductor scar rather long but small and narrow.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E50FFAC041DFDE0B5E9C8F7.taxon	discussion	REMARKS This genus is distinguished from other Lucinidae by the extremely flat valves, the long but narrow diverging part of the anterior adductor scar, the small umbo, the regular commarginal sculpture and the more or less leafy prolongations of the commarginal ridges on the dorsal margin. The most closely similar genus may be Lamellolucina Taylor & Glover, 2002, which has more tumid shells, more widely spaced lamellae, a crenulate margin and a shorter diverging part of the anterior adductor scar. That genus is mainly Indo-Pacific with L. reyrei (Nicklès, 1955) being the only tropical West African species.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E51FFAB07A2FD26B5F3CB13.taxon	description	(Figs 1; 2 A; 4)	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E51FFAB07A2FD26B5F3CB13.taxon	materials_examined	TYPE MATERIAL. — The material present in MNHN on which the description of L. gaini n. comb. is based were not specifically designated as types, it consists of three right valves and one left valve from the Bissagos Archipelago (Guinea-Bissau) and one left valve from Conakry (Guinea), these were to be considered as syntypes. As Lamy (1920) did not give a precise type locality, and as the specimen from Conakry belongs to another species (described in the next entry), the most typical specimen, and not the two smaller, figured specimens, from the Bissagos Islands lot is here selected as lectotype, and the other specimens are paralectotypes. The type locality is the locality cited by Lamy for this lot. TYPE LOCALITY. — Passage between Soga and Rouba, Bissagos Islands, Guinea Bissau. OTHER MATERIAL EXAMINED. — Guinea. Nearshore continental shelf, SEDIGUI cruises, 9 ° 03 ’ N- 9 ° 48 ’ N, 17 - 39 m, most taken by bottom grab, some by dredge, RV André Nizery, X. 1988, leg. R. von Cosel, V. 1988, 13 lots, sh. and v. (all MNHN). Ilha do Principe. Baia de Santo Antonio, entrance, 15 m, RV Calypso, Golfe de Guinée, stn P 14, numerous v. (MNHN). — Between Punta da Mina and Punta Novo Destino, 6 m, RV Calypso, Golfe de Guinée, stn P 7, 6 rv., 1 lv. (MNHN). — Praia de Santo Antonio, RV Calypso, Golfe de Guinée, stn P 22, 2 v. (MNHN). Equatorial Guinea. 01 ° 40 ’ S, 09 ° 25 ’ E, 150 m, in sediment core, communicated by S. Gofas, 1 rv. (MNHN). Gabon. Cap Esterias, Pointe Idolo, on sandbank, 14. XI. 1988, leg. R. von Cosel, 1 small chipped rv. (MNHN).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E51FFAB07A2FD26B5F3CB13.taxon	distribution	DISTRIBUTION. — Senegal (Dakar) to Guinea (Sierra Leone border) and Gabon; Sao Tomé, Ilha do Principe.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E51FFAB07A2FD26B5F3CB13.taxon	description	DESCRIPTION Shell small, 9 - 20 mm, rather thin but appearing solid, subcircular to circular, almost as long as high (length / height ratio 1.13 - 1.15), slightly inequilateral, equivalve, very compressed. Beaks just in front of the vertical midline. Anterior part broadly rounded, with a shallow inflexion between the middle part and the rounded corner to the antero-dorsal margin which is straight. Postero-dorsal margin slightly convex, posterior margin rounded, with a more or less indistinct, rounded postero-dorsal corner. Ventral margin well and evenly rounded. Exterior with regular, fine and thin commarginal lamellae (about 40 - 55 in large specimens) which on the very early part are more closely spaced than on the disk. Interspaces smooth. Part of the lamellae becoming more lamellate to foliate on the anterodorsal and postero-dorsal margins. Postero-dorsal area separated by a rather broad and shallow radial depression. Antero-dorsal area small, delimited by a sharp groove which also separates the disk sculpture with commarginal ridges from the foliate sculpture. Hinge plate moderately narrow, right valve with a single small cardinal tooth, no lateral. Left valve with one anterior and one posterior simple cardinal, no laterals. Lunule very short, broad and heart-shaped, somewhat assymmetrical, laterally slightly more prominent in the right valve, deeply inset; escutcheon long and extremely narrow, almost nonexistent. Anterior adductor scar small and narrow, with moderately long ventral part separate from the pallial line, this latter meeting the muscle impression almost in the middle. Inner margin of valves smooth. Valves entirely white; periostracum not seen. Measurements are provided in Table 1. BIOTOPE In fine, more or less muddy sand, from shallow water to about 30 m.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E51FFAB07A2FD26B5F3CB13.taxon	discussion	REMARKS Lamylucina gaini n. comb. is characterized by the very flat valves, the commarginal lamellae with clearly defined interspaces which are broader than the lamellae, and the well marked prolongations of these lamellae on the antero-and postero-dorsal keel.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E57FFA7041DFA5FB36FCF66.taxon	description	(Figs 2 B, C; 3; 4)	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E57FFA7041DFA5FB36FCF66.taxon	materials_examined	TYPE MATERIAL. — Holotype: Guinean continental shelf, W of Kaporo, 9 ° 42 ’ N, 15 ° 21 ’ W, 32 m, RV André Nizery, SEDIGUI, stn 344, 22. V. 1988, complete shell (MNHN). Paratype: same locality, 1 rv. (MNHN). TYPE LOCALITY. — Kaporo, Guinea.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E57FFA7041DFA5FB36FCF66.taxon	etymology	ETYMOLOGY. — The fact that this species was hitherto always identified as L. gaini n. comb. is expressed in the name. OTHER MATERIAL EXAMINED. — Senegal. Dakar region, S of Gorée, 110 - 112 m, dredged RV Gérard Tréca, 18. II. 1954, leg. I. Marche-Marchad, 1 rv. (MNHN). — Same locality, 95 - 98 m, 1 lv. (MNHN). — Dakar region (no details), 129 - 150 m, dredged RV Gérard Tréca, 24. I. 1958, leg. I. Marche-Marchad, 1 rv., 1 lv. (MNHN). — N Casamance, 12 ° 44.5 ’ N, 17 ° 37.3 ’ W, 40 m, dredged RV Louis Sauger, III. 1988, leg. R. von Cosel, 1 rv., 1 lv. (MNHN) — N Casamance, Kafountine, 12 ° 57.5 ’ N, 17 ° 16.8 ’ W, 35 m, dredged RV Louis Sauger, III. 1988, leg. R. von Cosel, 3 lv. (MNHN).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E57FFA7041DFA5FB36FCF66.taxon	materials_examined	Guinea-Bissau. Southern part, 11 ° 11 ’ N, 16 ° 59 ’ W, 26 m, dredged RV André Nizery, 22. IV. 1988, leg. R. von Cosel, 1 rv. (MNHN). Guinea (Conakry). Conakry (no details, paralectotype of Phacoides gaini Lamy, 1920), 1 lv. (MNHN). — Guinean continental shelf, SEDIGUI cruises, 9 ° 03 ’ N- 10 ° 12 ’ N, 24 - 57 m, bottom grab or dredge, RV André Nizery, V. 1988 and X. 1988, leg. R. von Cosel, 36 lots with numerous sh. and v. (MNHN). Sierra Leone. Off Sherbro Island, 7 ° 15.5 ’ N, 12 ° 61 ’ W, 64 m, dredged RV Calypso, Golfe de Guinée, stn 10, 14. V. 1956, leg. I. Marche-Marchad, 1 rv., 3 lv. (MNHN). Côte d’Ivoire. Abidjan region (no precision), leg. I. Marche-Marchad, 1 lv. (MNHN). Ghana. 4 ° 37 ’ N, 0 ° 50 ’ W, 90 - 100 m, dredged RV Calypso, Golfe de Guinée, stn 26, 24. V. 1956, leg. I. Marche- Marchad, 1 rv. (MNHN). Ilha do Principe. Off Praia Grande, 12 m, dredged RV Calypso, Golfe de Guinée, stn P 17, 3. VII. 1956, leg. I. Marche-Marchad, 1 rv. (MNHN). São Tomé. Off Praia Lagarto, 5 - 6 m, dredged RV Calypso, Golfe de Guinée, stn T 18, leg. I. Marche-Marchad, 11. VI. 1958, 1 rv. (MNHN). Gabon. Cap Esterias, Pointe Idolo, on sandbank, 14. XI. 1988, leg. R. von Cosel, 1 v. (MNHN). — Port- Gentil, Plage de la Sogara, beachdrift, 11. I. 2004, leg. R. von Cosel, 2 v. (MNHN). DISTRIBUTION. — Senegal (Dakar region) to Gabon, São Tomé, Ilha do Principe. DESCRIPTION Shell small, 9 - 20 mm, rather thin but appearing solid, circular, almost as long as high (length / height ratio 1.0 - 1.1), slightly inequilateral, equivalve, very compressed. Beaks about in or just in front of the vertical midline. Anterior part broadly rounded, with a very shallow inflexion between the middle part and the rounded corner to the short anterodorsal margin. Postero-dorsal margin more or less convex, posterior margin evenly rounded, with an indistinct, rounded postero-dorsal corner. Ventral margin rounded. Exterior with more or less irregular, fine, very densely spaced and thin, rounded commarginal ridges or cords, giving the surface a somewhat glossy appearance. Occasionally narrow, smooth interspaces. Ridges in the middle part coalescing in some specimens resulting in some nearly smooth areas. Only few of the commarginal cords may become lamellate or somewhat foliate on the anterodorsal and postero-dorsal margin. Occasionally some deeper incised growth stages. Postero-dorsal area separated by a broad and very shallow radial depression. Antero-dorsal area very small and narrow, delimited by a sharp groove. Hinge plate moderately narrow, right valve with a single small cardinal, no lateral. Left valve with one anterior and one posterior simple cardinal, no laterals visible. Hinge teeth very shallow and often reduced to completely missing. Lunule very small FIG. 4. — Distribution of Lamylucina gaini (Lamy, 1920) n. comb. (★) and Lamylucina exgaini n. gen., n. sp. (●) on the continental shelf of Guinea. Light grey area marks the sandy-muddy bottom, the clear area is pure sand, partly with gravel and shell debris. and heart-shaped, assymmetrical, laterally slightly more prominent in the right valve, deeply inset; escutcheon almost nonexistent. Anterior adductor scar very small and narrow, with moderately long and narrow ventral part separate from the pallial line, the latter meeting the muscle impression above the middle. Inner margin of valves smooth. Valves entirely white; periostracum not seen. Measurements are provided in Table 2. BIOTOPE Fine and mixed sand, without muddy components, mostly from about 25 m downward to 150 m, only on the coast of Gabon and the islands of the Gulf of Guinea in shallower water. REMARKS Lamylucina exgaini n. gen., n. sp. is similar to L. gaini n. comb., with which it was previously confused. The principal difference from L. gaini n. comb. is the external sculpture with the much more close-set commarginal sculpture consisting of fine rounded and broader cords rather than ridges or lamellae. These cords often touch each other or even merge to a certain extent, whereas in L. gaini n. comb., the lamellae always have more or less large, clearly defined interspaces. In contrast to L. gaini n. comb., the leaf-like prolongations of a part of the commarginal ridges are very much reduced or absent, and the postero-dorsal margin is often more sloping; with the valves thus appearing subcircular. The anterior adductor scar, especially its diverging part is somewhat narrower. The cardinals are less developed and may be completely absent. Both species were encountered sympatrically in some places (Gabon, Ilha do Principe), without intergrades. During the SEDIGUI cruises on the Guinean shelf, L. gaini n. comb. was found in more inshore waters on fine sandy substrates but always with a more or less high portion of mud, whereas L. exgaini n. gen., n. sp. is confined to more offshore localities, living in sandy bottom without mud (see Fig. 4). The two species have clearly different sediment preferences, and in certain localities like the Guinean shelf, they also seem to prefer different depths but this is not always the case.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5BFFA707CDFEA2B25FCF45.taxon	materials_examined	TYPE SPECIES. — Tinalucina aequatorialis n. sp. SPECIES INCLUDED. — Tinalucina aequatorialis n. sp.; T. inanis (Prashad, 1932) n. comb.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5BFFA707CDFEA2B25FCF45.taxon	etymology	ETYMOLOGY. — Dedicated to my colleague Tina Molodtsova in acknowledgement of her work-up of the collection of antipatharians of MNHN.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5BFFA707CDFEA2B25FCF45.taxon	distribution	DISTRIBUTION. — Inner Gulf of Guinea, tropical West Africa, and Indo-West Pacific (Sumbawa, Indonesia).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5BFFA707CDFEA2B25FCF45.taxon	diagnosis	DIAGNOSIS. — Shells small, mostly under 10 mm, variable in outline, subcircular, slightly longer than high to almost as long as high, moderately tumid, with a broad anterior and posterior part and a more or less truncated, very slightly or not indented posterior margin. Anterior margin more convex in its middle part. Beaks in or just in front of the vertical midline. Umbones rather prominent. Surface with more or less developed, densely spaced fine commarginal lamellae, which may be obsolete on the middle part of the disk. Antero-dorsal area small and hardly separated, a depression may be visible. Posterior angle rounded, postero-dorsal depression broad and shallow but well developed. Lunule small, not too narrow, only slightly asymmetrical. Escutcheon entirely filled with the ligament. Hinge plate more or less narrow, with slight vestiges of one or two cardinals. Diverging part of anterior adductor scar short and broad, with a length of about half the total length of the scar. Inner margins smooth.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5BFFA707CDFEA2B25FCF45.taxon	discussion	REMARKS The species of this genus are characterized by a combination of features: small size, nearly equal-sized adductor scars with the short and broad anterior adductor with short diverging part, well set-off posterior area and somewhat irregular surface of the valves. The other species in the genus is Tinalucina inanis n. comb., which was placed in Dentilucina (Dentilucina) by Prashad (1932). Dentilucina P. Fischer, 1887 (type species: Venus jamaicensis Spengler, 1784), however, is an objective synonym of Phacoides Agassiz, 1845. The two species united in the new genus Tinalucina n. gen. demonstrate again a close relationship between the molluscan fauna of tropical West Africa and that of the Indo-West Pacific realm.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5BFFA40436FE82B50BCB53.taxon	description	(Figs 5; 6 A, B)	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5BFFA40436FE82B50BCB53.taxon	materials_examined	TYPE MATERIAL. — Holotype: Equatorial Guinea, W of Bioko Island (formerly Fernando Poo), off the coast of Cameroon, 3 ° 50 ’ 20 ” N, 8 ° 21 ’ 40 ” E, 98 m, in silty bottom, a fresh empty shell, taken by corer, Gardline Survey 2003, stn VIO 2, 6.8 × 6.0 × 3.0 mm (BMNH 20040254). TYPE LOCALITY. — Bioko (formerly Fernando Poo), Equatorial Guinea.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5BFFA40436FE82B50BCB53.taxon	etymology	ETYMOLOGY. — After Equatorial Guinea, in which the type locality is situated.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5BFFA40436FE82B50BCB53.taxon	distribution	DISTRIBUTION. — Inner Gulf of Guinea, only known from the type locality and possibly restricted to the Cameroon deeper shelf and adjacent islands.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5BFFA40436FE82B50BCB53.taxon	description	DESCRIPTION Shell very small (holotype 6.8 mm long), rather thick and solid, equivalve, moderately inflated, subcircular but more tending to rectangular-polygonal, slightly longer than high, length / height ratio 1.1. Umbones prominent, beaks slightly in front of the vertical midline. Antero-dorsal (lunular) margin markedly concave, antero-dorsal corner narrowly rounded, well marked. Anterior margin rounded, more so on its middle part, ventral margin rounded, less convex in its middle part. Posterior margin nearly vertically truncated, with a very slight sinuosity in the middle and with broadly rounded postero-dorsal and postero-ventral corners. Exterior somewhat irregular, with irregularly but mostly densely-spaced, shallow, commarginal lamellae and a few growth lines. Anterior angle almost absent, anterior radial depression obsolete, antero-dorsal area indistinct. Posterior angle rounded, posterior radial depression broad and well defined, ending in a very shallow indentation of the posterior margin. Lunule small, moderately narrow, slightly asymmetric, longer than broad, a little sunken; escutcheon absent, ligament deeply sunken. Hinge plate narrow but strong, right valve with a rudimentary single cardinal tooth, an anterior New taxa of tropical West African Lucinidae (Mollusca, Bivalvia) lateral and vestiges of a posterior lateral. Left valve with two small cardinals, an anterior lateral and the vestiges of a posterior lateral. Anterior adductor scar rather short, with short and broad diverging part, the pallial line meeting the scar slightly above its middle. Inner margin smooth. Valves entirely white, periostracum thin and almost colourless, eroded on large parts of the valves.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5BFFA40436FE82B50BCB53.taxon	discussion	REMARKS The only comparable species is the Indo-Pacific T. inanis n. comb. (see Fig. 6 C), which grows only slightly larger than T. aequatorialis n. gen., n. sp., up to 10 mm; it is further distinguished by the smooth middle part of the valves, however, both species share the somewhat irregular valve surface, the general shell outline, the hinge dentition and the equi-sized adductor scars. The only other very small tropical West African lucinid species, Loripes (Keletistes) legouxi (Nicklès, 1952) (Fig. 6 D), is easily distinguished by its internal ligament and its much more tumid valves. Tinalucina aequatorialis n. gen., n. sp. was found together with juveniles of Afrolucina discontinua n. gen., n. sp. (described herein, see below) of about the same size.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E58FFA20428FA98B03ACA3D.taxon	materials_examined	TYPE AND ONLY SPECIES. — Lucina leloeuffi Cosel, 1989.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E58FFA20428FA98B03ACA3D.taxon	etymology	ETYMOLOGY. — In spite of the differences, at a first glance and external view, the valves resemble a Lucinoma, and this is expressed in the name (falsus, Latin = false).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E58FFA20428FA98B03ACA3D.taxon	distribution	DISTRIBUTION. — Northern Gulf of Guinea, tropical West Africa.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E58FFA20428FA98B03ACA3D.taxon	diagnosis	DIAGNOSIS. — Shells large, subcircular-triangular, compressed, with short and conspicuously rostrate anterior part and broad and longer posterior part. Anterior and posterior area well demarcated. Surface with 10 - 15 conspicuous, thin, raised and widely spaced commarginal lamellae and smooth interspaces. Lunule very small and short, slightly asymmetric, escutcheon long and deeply sunken, delimited by a keel and almost entirely filled by ligament. Hinge plate narrow, left valve with two cardinal teeth, a strong anterior lateral and a smaller, narrower knob above it, and a narrow posterior lateral; right valve with two cardinals, two anterior laterals and two posterior laterals. Ligament short. Adductor scars small for the shell size, diverging part of anterior adductor scar very short and rather narrow, tapering; pallial line meeting the scar about in its middle. Inner margins smooth, but radial wavy sculpture on the zone between pallial line and margin and occasionally a few vestiges of irregular crenulations.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E58FFA20428FA98B03ACA3D.taxon	discussion	REMARKS This genus is characterized by the strong anterior and posterior laterals in both valves, the small anterior adductor scar with the short and narrow diverging part and the short and rostrate anterior part of the shell. Externally it reminds a Lucinoma, with which it has in common the toothed hinge and the lamellose exterior with well separated anterior and posterior areas. There are also Lucinoma species with rostrate anterior margins (e. g., in this paper), but to a lesser extent. Moreover, the very much forward placed umbones, the more conspicuously rostrate anterior margin and the very small diverging part of the anterior adductor scar clearly distinguish Falsolucinoma n. gen. The highly asymmetric lunule and the short anterior adductor scar place the genus closer to the Myrtea group; however, species of Myrtea are smaller and often more tumid with their characteristicelly raised escutcheonal keel, often with tiny and dense spines. Their outline is more regular with the umbones placed less forward. There is only one other genus known which has a similarly short and rostrate anterior part and a very short diverging part of the anterior adductor scar. It occurs in the Indo-West Pacific and will be published elsewhere (Cosel & Bouchet unpubl. data). Species of that genus, however, are more elongate, they have very densely spaced commarginal lamellae, the diverging lower part of the anterior adductor scar is much broader, and their hinge plate is narrower and almost toothless. The genus most similar to Falsolucinoma n. gen. is Lamellolucina Taylor & Glover, 2002, which is predominantly Indo-West Pacific, but one species, L. reyrei (Nicklès, 1955) occurs in West Africa. It is also characterized by prominent and more or less widely spaced commarginal lamellae, a similar hinge dentition with strong laterals and a generally rather short extension of the anterior adductor scar. Falsolucinoma n. gen. differs in the absence of a regularly crenulate margin, the more foreward placed umbones, the less asymmetric lunule and the much larger size.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5EFFA00741FB79B295C8F7.taxon	description	(Figs 7; 8)	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5EFFA00741FB79B295C8F7.taxon	materials_examined	TYPE MATERIAL. — Holotype: E Liberia, off Cap des Palmes, c. 4 ° 10 ’ N, 7 ° 40 ’ W, 250 m, dredged RV Reine Pokou, 13. X. 1971, leg. Le Loeuff (IRD), 1 lv. (MNHN). Paratypes: same locality, 2 lv. (MNHN). TYPE LOCALITY. — Cap des Palmes, E Liberia, tropical West Africa. OTHER MATERIAL EXAMINED. — Cameroon. 1 spm (MNHN) taken by RV Fridtjof Nansen during a cruise off the coast of Cameroon for FAO purpose. Data of the specimen unknown.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5EFFA00741FB79B295C8F7.taxon	distribution	DISTRIBUTION. — Gulf of Guinea, apparently from western Côte d’Ivoire to Cameroon.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5EFFA00741FB79B295C8F7.taxon	description	DESCRIPTION Shell large, up to 56 mm long, length / height ratio 1.2, relatively thin-shelled, but solid, inequilateral, compressed, subcircular-triangular-rostrate, slightly variable in outline and length / height ratio. Beaks situated at or just behind the anterior third of the valve. Anterior part triangular-rostrate, anterior margin pointed. Posterior part broad, posterior margin obliquely truncate. Postero-dorsal corner rather broadly rounded. Antero-dorsal margin nearly straight, postero-dorsal margin slightly convex. Ventral margin behind the anterior point slightly concave, then to postero-ventral corner evenly rounded, this latter narrowly rounded. Exterior with 10 - 15 conspicuous, prominent, thin, raised and widely spaced commarginal lamellae: 15 in the holotype, 10 and 14 in the paratypes, which on the early and middle part of the valves are evenly spaced, and may become slightly more closely spaced ventrally. Interspaces smooth, with shallow commarginal growth waves. Posterior area with a broad and shallow radial depression, separated from the disk by a broadly rounded posterior angle. Anterior area with a well marked and sharp radial depression, ending in a sinuosity in the upper anterior margin. Anterior angle narrowly rounded. Hinge plate narrow, in the left valve with a small anterior cardinal and a narrow lamellar posterior cardinal, a strong anterior lateral and a narrow and long posterior lateral and above both more or less strong, tooth-like reinforcements. Right valve with a short, thick, bifid and only slightly inclined anterior cardinal and a thin, oblique posterior cardinal. Two anterior laterals with a deep depression between them; lower lateral more forward placed than upper lateral. Lower posterior lateral narrow but rather strong, upper posterior lateral thin and much weaker. Ligament short. Lunule very short and small, deeply sunken, slightly asymmetric, escutcheon almost entirely filled by the ligament. Adductor scars small, anterior scar with short, rather narrow and somewhat tapering diverging part, pallial line meeting the scar about in its middle. Inner margin of valves not visibly and regularly crenulate but with shallow radial waves on the zone between pallial line and margin and sometimes a few vestiges of irregular crenulations. Valves entirely white; periostracum rather strong, almost white-translucent to pale straw-coloured or brownish, often peeling off in the interspaces of the lamellae. Measurements are provided in Table 3.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5EFFA00741FB79B295C8F7.taxon	discussion	REMARKS As for the genus. The most similar looking species is Lamellolucina jawa Taylor & Glover, 2002, from Madura, Indonesia. It has a similar general shell shape, a similar hinge dentition and also extremely small adductor scars but is distinguished by the smaller size, the more circular outline, the presence of a finely and regularly crenulate margin and much more densely spaced commarginal lamellae. Falsolucinoma leloeuffi n. comb. was described only from three right valves, but fortunately now a single complete live-collected specimen, albeit without any precise data, became available. It was trawled by the RV Fridtjof Nansen in the Gulf of Guinea, apparently off Cameroon; the known range is thus extended considerably eastward.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5DFFA107C8FF0CB5FCCF05.taxon	materials_examined	TYPE AND ONLY SPECIES. — Afrolucina discontinua n. sp.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5DFFA107C8FF0CB5FCCF05.taxon	etymology	ETYMOLOGY. — The name reflects that this genus was discovered on the African shelf.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5DFFA107C8FF0CB5FCCF05.taxon	distribution	DISTRIBUTION. — Tropical West Africa.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5DFFA107C8FF0CB5FCCF05.taxon	diagnosis	DIAGNOSIS. — Shells small, subcircular, slightly longer than high, rather compressed. Beaks slightly in front of the vertical midline. Surface with numerous fine and more or less densely spaced commarginal lamellae, umbonal area appearing smooth. Interspaces with very fine growth lines. Antero-dorsal angle very shallow, anterior area well marked. Postero-dorsal area separated by a rounded posterior angle. Lunule short, broad, markedly asymmetrical, in the right valve broad, in the left valve very narrow, sunken. Escutcheon long, narrow and sunken. Hinge line curved, hinge with one small, well defined cardinal tooth in the right valve and two in the left valve. Anterior and posterior lateral teeth in the right valve indistinct, in the left valve almost obsolete. Anterior adductor scar rather elongate, with diverging part about half its length or slightly shorter. Posterior adductor scar small. Inner margins smooth.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5DFFA107C8FF0CB5FCCF05.taxon	discussion	REMARKS This genus is most similar to a group of deeper water lucinids from the Indo-Pacific discussed in detail by Cosel & Bouchet (unpubl. data), which comprises some new genera, however, none of them are really identical to Afrolucina n. gen. This Indo-Pacific group has superficial resemblance to Lucinoma, but that genus is characterized by the presence of well developed hinge teeth and a long and slender diverging part of the anterior adductor scar which meets the pallial line near the upper (dorsalward) end of the impression. The species of the group here discussed have a nearly edentulous hinge, whereas in the West African Afrolucina discontinua n. gen., n. sp., small cardinals are present. The spectacular lunular asymmetry indicates affinities of Afrolucina n. gen. to the Myrtea group and is not seen as this in the Indo-West Pacific genera. All genera, however, share a much shorter and broader diverging part of the anterior adductor scar, which is met by the pallial line in its middle, another character of the Myrtea group. The genus Tinalucina n. gen. is distinguished by the more tumid valves, the more protruding um- bones, the more regular commarginal sculpture, the more equal-sized adductor scars with short and broad diverging part of the anterior one, the less asymmetrical lunule and the smaller shell size.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5DFFBD042CFE41B000CB91.taxon	description	(Figs 9 - 11)	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5DFFBD042CFE41B000CB91.taxon	materials_examined	TYPE MATERIAL. — Holotype: Côte d’Ivoire, off Grand Bassam, 70 m, dredged RV Reine Pokou, 1977, leg. Le Loeuff (IRD), 1 fresh sh. (MNHN). Paratypes: Abidjan region (no more precision), dredged RV Reine Pokou, 1965 - 1974, leg. Le Loeuff, 2 sh., 1 juv. sh., 2 lv. (MNHN); 1 sh., 1 rv. (BMNH). TYPE LOCALITY. — Grand Bassam, Côte d’Ivoire.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5DFFBD042CFE41B000CB91.taxon	etymology	ETYMOLOGY. — This species is a good example of the several West African species with a disjunct distribution, and that is expressed in the name. OTHER MATERIAL EXAMINED. — Senegal. Dakar, 14 ° 43 ’ N, 17 ° 30 ’ W, 205 - 230 m, dredged RV Gérard Tréca, 18. III. 1958, leg. I. Marche-Marchad, 1 rv., 1 lv. (MNHN). — 14 ° 51.5 ’ N, 17 ° 30 ’ W, 180 - 165 m, dredged RV Gérard Tréca, 18. III. 1958, leg. I. Marche-Marchad, 1 rv., 2 lv., 1 fragm. (MNHN). — Baie de Gorée, 80 - 250 m, dredged RV Gérard Tréca, 20. II. 1956, leg. I. Marche-Marchad, 1 chipped lv. (MNHN). — S of Gorée, 95 - 98 m, dredged RV Gérard Tréca, 18. II. 1954, leg. I. Marche-Marchad, 1 lv. (MNHN).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E5DFFBD042CFE41B000CB91.taxon	materials_examined	Liberia. Near the border to Côte d’Ivoire, 4 ° 31.5 ’ N, 8 ° 31 ’ W, 64 m, dredged RV Calypso, 20. V. 1956, 1 lv., 1 rv. (MNHN). Côte d’Ivoire. Abidjan region (no precision), 100 m, dredged RV Reine Pokou, leg. Le Loeuff, 1 juv. v. (MNHN). — 4 ° 27.5 ’ N, 7 ° 09 ’ W, 50 m, dredged RV La Rafale, 6. IV. 1964, leg. G. Cherbonnier, 1 juv. rv. (MNHN). — Off S. Pedro, 4 ° 36 ’ N, 6 ° 33 ’ W, 100 m, dredged RV La Rafale, 7. IV. 1964, leg. G. Cherbonnier, 1 spm (MNHN). — Off Grand Bassam, 5 ° 04.0 ’ N, 3 ° 45.8 ’ W, 64 m, dredged RV Antéa, 16. VIII. 1998, leg. R. von Cosel, 1 juv. lv. (MNHN). Equatorial Guinea. W of Bioko Island (formerly Fernando Poo), off the coast of Cameroon, 3 ° 50 ’ 20 ” N, 8 ° 21 ’ 40 ” E, 98 m, in silty bottom, taken by corer, Gardline Survey 2003, stn VIO 2, 1 juv. sh. (BMNH). — Same region, 4 ° 01 ’ 16 ” N, 8 ° 36 ’ 06 ” E, 70 m, taken by corer, Gardline Survey 3003, stn NEA-I, 1 juv. sh. (BMNH). — Same region, 4 ° 00 ’ 45 ” N, 8 ° 24 ’ 15 ” E, 74 m, taken by corer, Gardline Survey 3003, stn BOC 3 FC, 1 juv. sh. (BMNH). Congo (Brazzaville). N’Kossa oilfield, 5 ° 53.12 ’ S, 11 ° 38.30 ’ E, 200 m, leg. L. Bigot, 23. IX. 1995, 1 rv. (MNHN). Northern Angola. Ambrizete, 80 m, 1982 - 1986, leg. S. Gofas, 1 juv. rv. (MNHN). — Ilha de Luanda, 120 m, 1982 - 1986, leg. S. Gofas, 1 rv., 3 lv. (MNHN). — Off Mussulo, 90 - 100 m, 1982 - 1986, leg. S. Gofas, 1 rv. (MNHN). — Palmeirinhas, 60 - 80 m, 1982 - 1986, leg. S. Gofas, 7 rv., 3 lv. (MNHN). Second morph, somewhat longer and regular commarginal lamellae: Bénin. Off Ouidah, 6 ° 10 ’ N, 2 ° 05 ’ E, 200 m, dredged RV Léon Coursin, 22. XI. 1958, leg. I. Marche-Marchad, 3 rv., 2 lv. (MNHN). Nigeria. Off Niger delta, 4 ° 05 ’ N, 5 ° 28 ’ E, 90 - 105 m, dredged RV Calypso, 26. V. 1956, 1 lv. (MNHN). Northern Angola. Ilha de Luanda, 120 m, leg. S. Gofas, 1 lv. (MNHN). DISTRIBUTION. — Senegal (Dakar); Côte d’Ivoire to inner Gulf of Guinea (northern Cameroon, Bioko); northern Angola (Luanda). Not recorded from Guinea-Bissau to Liberia (border to Côte d’Ivoire) and from southern Cameroon to the Congo Republic which may indicate distribution gaps in the tropical zone proper. DESCRIPTION Shell 12 - 18 mm long, rather solid, somewhat variable in outline and sculpture, subcircular (length / height ratio 1.1), inequilateral, equivalve, compressed. Beaks just in front of the vertical midline. Anterior margin with a slight but rather sharp corner to the antero-dorsal margin. Anterodorsal margin divided into two short, concave to almost straight parts with a corner between them, the upper part comprising the lunular area. Posterior margin obliquely truncated, with rounded corners. Postero-dorsal margin slightly convex. Ventral margin well rounded. Exterior with numerous thin, more or less denselyspaced commarginal lamellae, which are often eroded and which may be obsolete on the first umbonal 10 mm of the valve, with surface appearing smooth. Interspaces with very fine growth lines. Antero-dorsal area well separated, with denser commarginal lamellae and wrinkles and a shallow radial depression in the middle. Postero-dorsal area separated by a rounded posterior angle. Hinge plate narrow, hinge with one small but generally distinct oblique cardinal tooth in the right valve and two in the left valve. Anterior and posterior laterals in the right valve appearing as very small and indistinct knobs, in the left valve almost obsolete. Lunule short and rather broad, markedly asymmetrical, sunken; left valve with a strong and more or less protruding lunular plate which inserts directly under the much narrower lunular plate of the right valve into a socket under and parallel to it (Fig. 9 E, F). Anterior cardinal of the left valve partly or completely integrated into the lunular plate. Escutcheon long, narrow and sunken. Anterior adductor scar fairly small, with short ventral part separate from the pallial line, this latter meeting the scar about in its middle or just before it. Pallial line often divided into a line of close-set separate impressions (Fig. 11 B). Inner margin of valves smooth. Colour of valves entirely white, periostracum very thin, yellowish brown, on the earliest part of the valves thinner to obsolete. There exists a second “ morph ”, of which a few valves were collected off Bénin, Nigeria and off northern Angola (Fig. 10). The valves have regular and rather densely spaced commarginal lamellae over the whole valve surface and are occasionally slightly more elongate. As very little material is available, and as there might be intergrades to the “ normal ” form, I leave them as a variety within A. discontinua n. gen., n. sp. Measurements are provided in Table 4. BIOTOPE In soft sediment, most probably fine muddy sand, from 50 to about 230 m. REMARKS In outline, this species resembles somehow Graecina karinae n. gen., n. sp. (see next entry) but is easily distinguished by the sharp antero-dorsal corner, the obliquely truncated posterior margin, the sculpture, the often interrupted pallial line and the smaller size. The distributional range of Afrolucina discontinua n. gen., n. sp. coincides with the different zones of seasonal upwelling on the coast of tropical West Africa: Senegal in the Northern zone of Alternance (see Intés & Le Loeuff 1984; Le Loeuff 1993; Le Loeuff & Cosel 1998) with strong upwelling during northern winter, Côte d’Ivoire and Bénin in the central atypical tropical zone with intermittent seasonal upwelling and Angola in the Southern zone of Alternance with upwelling in southern winter. The species seems not to be present in the northern (Guinea to Liberia) and southern (southern Cameroon to Gabon) typical tropical zones and also not in the zones with weaker upwelling adjacent to the zones of Alternance (Guinea-Bissau in the North and Congo in the South). However, recently a few very small specimens were found west of Bioko (Fernando Poo), which is already in the southern typical tropical zone and within the influence of the Niger delta. The species may need some regular influence of upwelling.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E41FFBA07C0F9DFB025CC3A.taxon	materials_examined	TYPE AND ONLY SPECIES. — Graecina karinae n. sp.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E41FFBA07C0F9DFB025CC3A.taxon	distribution	DISTRIBUTION. — Northern Angola (Ambrizete), tropical West Africa.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E41FFBA07C0F9DFB025CC3A.taxon	diagnosis	DIAGNOSIS. — Shells medium-sized, subcircular, slightly longer than high, rather compressed. Beaks in front of the vertical midline. Surface with thin commarginal lamellae or cords only on the earlier part of the valves, becoming obsolete and then absent ventrally. Rest of the valves with growth lines and some coarser “ growth stages ”. Anterior area with two shallow radial depressions, anterior angle indistinct. Postero-dorsal area indistinct and not separated by a visible posterior angle. Lunule long, narrow, slightly asymmetrical, sunken. Escutcheon long, narrow and sunken, delimited by a sharp and prominent, narrowly laminate keel, but no long lamellate prolongations. Hinge arched, in the right valve with one well developed cardinal tooth and sometimes the vestiges of a posterior cardinal, and anterior and posterior laterals. Left valve with two cardinals and well marked anterior and posterior laterals. Anterior adductor scar rather elongate, with moderately long diverging part, pallial line meeting the scar in about its middle or just above it. Posterior adductor scar small. Inner margins smooth.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E41FFBA07C0F9DFB025CC3A.taxon	etymology	ETYMOLOGY. — The name goes back to Roman history as already does the name of the type genus of Lucinidae, Lucina (Lucina is the Roman goddess of childbirth). Lucina is believed to have been the baptismal name of Pomponia Graecina, a noble Roman lady and wife of the conqueror of Britain, Aulus Plautius. The new genus Graecina n. gen. honours the same person as the genus Lucina.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E41FFBA07C0F9DFB025CC3A.taxon	discussion	REMARKS This genus has an overall appearance of a large Myrtea; especially with its raised and sharp escutcheonal keel, however, the valves are much more compressed, and the anterior adductor scars are more elongate, with a longer diverging part. In shell form and outline and with the small posterior adductor scar, this genus looks most similar to a new genus under description by Cosel & Bouchet (unpubl. data), however, Graecina n. gen. is much larger, has well defined cardinal and lateral teeth and commarginal lamellae on the earlier part of the valves; the pallial line meets the anterior adductor scar at a higher point and thus leaves a longer ventral diverging part. Another genus, especially similar in size and form of the anterior adductor is also under description by Cosel & Bouchet (unpubl. data). In that genus, the hinge is toothless, the hinge line is less bent and the lunule is shorter.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E46FFB907C2FD67B04DCD38.taxon	description	(Figs 12; 13)	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E46FFB907C2FD67B04DCD38.taxon	materials_examined	TYPE MATERIAL. — Holotype: N Angola, Angola Margin, W of Ambrizete, 7 ° 18.42 ’ S, 12 ° 04.60 ’ E, 360 - 367 m, trawled RV Thalassa, ZAIANGO BIOL 2, stn CP 09, 29. VIII. 2000, leg. R. von Cosel, lv. (MNHN). Paratypes: same locality, 3 rv., 1 lv. (MNHN); 2 rv. (BMNH). TYPE LOCALITY. — Ambrizete, Northern Angola, tropical West Africa.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E46FFB907C2FD67B04DCD38.taxon	etymology	ETYMOLOGY. — Dedicated to my colleague Karine Olu-Le Roy from IFREMER, in acknowledgement of her longtime kind collaboration on bivalves of cold seeps. OTHER MATERIAL EXAMINED. — Nigeria. S of Port Harcourt, 3 ° 42.28 ’ N, 7 ° 47.59 ’ W, 425 m, taken by corer, RV Le Suroît, stn GUINESS 2, 2. IX. 1993, leg. P. Cochonat, 2 fossilized lv., 1 rv. (MNHN).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E46FFB907C2FD67B04DCD38.taxon	materials_examined	Northern Angola. Angola Margin, off Ambrizete, 7 ° 18.42 ’ S, 12 ° 04.60 ’ E, 360 - 367 m, trawled RV Thalassa, ZAIANGO BIOL 2, stn CP 09, 29. VIII. 2000, leg. R. von Cosel, associated specimens, 6 lv., 9 rv., all old and partly chipped or worn (MNHN). DISTRIBUTION. — Nigeria; Northern Angola. DESCRIPTION Shell medium-sized, up to about 40 mm long, rather thick and solid, somewhat variable in outline, subcircular (length / height ratio 1.1), inequilateral, equivalve, rather compressed. Beaks well in front of the vertical midline. Anterior part broadly rounded, anterior margin evenly convex. Posterior part rounded, posterior margin convex but occasionally obliquely truncated, with rounded postero-ventral corner. Antero- and postero-dorsal margins sloping, with a curved hinge line; margin between the lunular area and the anterior margin strongly curved. Postero-dorsal margin convex, occasionally more so in its upper part behind the umbones. Ventral margin rounded, in the middle less convex. Exterior with thin commarginal lamellae or cords, only on the earlier third or fourth or sometimes the very earliest part of the valves, becoming obsolete and then absent towards ventrally. Interspaces with very fine growth lines only. Rest of the valves with strong, dense and rather regular growth lines and some coarser “ growth stages ”. Antero-dorsal area with two shallow radial depressions, one closely under the lunular area, the other somewhat more below it, anterior angle indistinct. Postero-dorsal area indistinct and not separated by a visible posterior angle. Hinge plate narrow and arched. Hinge in the right valve with one well developed cardinal tooth and sometimes the vestiges of a posterior cardinal, and long and narrow anterior and posterior laterals. Left valve with one well developed cardinal and a narrow and short anterior cardinal, and narrow, well marked anterior and posterior laterals. Lunule rather long, narrow, slightly asymmetrical, somewhat broader in the right valve, sunken. Escutcheon long, narrow and sunken, delimited by a sharp, raised and serrated keel, but no highly lamellate prolongations. Anterior adductor scar rather small, long, with moderately long diverging part, pallial line meeting the scar in about its middle or just above it. Posterior scar small but rather broad. Inner margin of valves smooth. Valves presumably white in life but in the dead collected samples chalky or light greyish. Periostracum thin, light greenish brown, when present. Measurements are provided in Table 5. BIOTOPE All collected specimens are rather aged single valves. They were trawled, together with complete shells and / or valves of two other lucinid species, also described herein (see below), on a site at the Angola shelf margin (ZAIANGO Program, site B) where about 20 to 45 m high, circular mounds of deep water coral (Lophelia pertusa (Linnaeus, 1758 )) are present (Dekindt et al. 2001; Olu-Le Roy pers. comm.). On these mounds, living corals are on top and on the higher parts, whereas dead corals and debris are found on the lower part and at the bases. The lucinid shells and valves were on the sediment around and in depressions between the mounds. In the trawl, which had passed on an almost N-S line just at the base of coral mounds in a depth of 360 - 425 m, they came up as agglomerations of dead shells embedded in dark grey and very sticky mud, but none of the lucinids were collected alive or in very fresh state. Some valves had even pieces of solidified mud on them, which were difficult to remove. It is presumed that these Lucinidae species come from a site of reducing sediments where fluid emissions (methane or sulfide-rich) may still be slightly active or are no longer active, and where the fauna is dying out. REMARKS As for the genus.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E45FFB907DDFC65B01CC8F0.taxon	materials_examined	TYPE SPECIES. — Lucina filosa Stimpson, 1851, by original designation. SPECIES INCLUDED. — Numerous species, worldwide.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E45FFB907DDFC65B01CC8F0.taxon	diagnosis	DIAGNOSIS. — Shells medium-sized to very large, rather thin to strong and solid, very variable in outline, in general subcircular to somewhat triangular, but also almost circular to even short-oval. Anterior margin broadly rounded to more or less pointed. Umbones in front of the vertical midline. Surface with more or less pronounced commarginal ribs or lamellae and finer threads between them. Hinge with two well developed cardinal teeth in each valve and a small anterior lateral and often a small posterior lateral. Diverging part of the anterior adductor scar very long and more or less narrow.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E45FFB907DDFC65B01CC8F0.taxon	discussion	REMARKS Lucinoma is one of the most speciose lucinid genera; it is distributed worldwide, in tropical latitudes as well as in temperate and cold waters. In tropical West Africa, four species are known. More detailed comments on the genus will be given Cosel & Bouchet (unpubl. data).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E45FFB7046CFE01B30CCBF2.taxon	description	(Figs 14; 15 A, B)	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E45FFB7046CFE01B30CCBF2.taxon	materials_examined	TYPE MATERIAL. — Figured syntype: Cap Verde Islands, near Maio, 15 ° 14 ’ N, 23 ° 04.1 ’ W, 628 m, muddy sand, trawled RV Princess Alice, 14. VIII. 1901, 1 complete sh. (MOM); same locality, 3 other syntypes: 2 sh., 1 worn rv. (all MOM). TYPE LOCALITY. — Maio, Cape Verde Islands.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E45FFB7046CFE01B30CCBF2.taxon	distribution	DISTRIBUTION. — Only known from the Cape Verde Islands.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E45FFB7046CFE01B30CCBF2.taxon	description	DESCRIPTION Shell 12 - 16 mm long, thick and solid, subcircular, inequilateral, equivalve, compressed. Beaks slightly in front of the vertical midline. Anterior margin rounded, posterior margin obliquely rounded-truncated with rounded corners. Postero-dorsal margin slightly convex. Ventral margin evenly semicircular. Exterior with numerous, very fine, irregular growth lines, occasionally more or less eroded on the umbonal part of the valves; commarginal lamellae only visible in the region of the posterior angle if at all. Earlier part of the valves appearing smooth. Posterior area delimited by gently rounded posterior angle, anterior angle absent. Hinge plate very broad, especially under the umbones, with a rather thin anterior and a strong posterior cardinal tooth in the right valve and a strong, slightly bifid anterior and a thinner and more laminar posterior cardinal in the left valve. Anterior laterals in both valves small and knob-like but well defined, posterior laterals ill-defined or obsolete. Lunule quite broad with thick layer of periostracum. Escutcheon long and narrow, ligament deeply inset. Anterior adductor scar rather small, its diverging part very long and narrow. Inner margin of valves smooth. Valves entirely white. Periostracum yellowish brown, on the earliest parts of the valve thin to obsolete (eroded). Measurements are provided in Table 6. BIOTOPE Muddy-sandy bottom on the shelf slope at about 600 m.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E45FFB7046CFE01B30CCBF2.taxon	discussion	REMARKS This species is the smallest West African Lucinoma, it is distinguished from the other Lucinoma of the region by the very broad hinge plate under the umbones, which, together with the concave lunular area, gives the beaks a more raised appearance.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E4BFFB507D0FA3FB544CA5E.taxon	description	(Figs 15 C, D; 16)	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E4BFFB507D0FA3FB544CA5E.taxon	materials_examined	TYPE MATERIAL. — Holotype: W of Mauritania, 20 ° 32 ’ N, 18 ° 36 ’ W, 2042 m, dredged RV Atalante, EUMELI 4, stn CP 16, 5. VI. 1992, an alcohol preserved spm (MNHN). Paratypes: same locality, 2 sh. (MNHN). TYPE LOCALITY. — Cape Verde Basin, W of Cap Blanc, Mauritania.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E4BFFB507D0FA3FB544CA5E.taxon	etymology	ETYMOLOGY. — Named after the RV Atalante, from which the type material was taken. OTHER MATERIAL EXAMINED. — Mauritania. W of Cap Blanc, 20 ° 41 ’ N, 18 ° 33 ’ W, 2114 m, dredged RV Atalante, EUMELI 2, stn CP 03, 5. II. 1992, 3 spm, 1 adult, 1 juv. sh. (MNHN). — 20 ° 33 ’ N, 18 ° 35 ’ W, 2003 m, dredged RV Atalante, EUMELI 2, stn CP 04, 5. II. 1992, 1 juv. sh. (MNHN). — NW of Cap Blanc, 20 ° 58.9 ’ N, 18 ° 13.6 ’ W, 2112 - 2160 m, RV Discovery, stn 9133 # 5, 25. II. 1976, 2 spm, 2 sh. (BMNH). — Same locality, 20 ° 57.0 ’ N, 18 ° 11.0 ’ W, 2110 - 2130 m, RV Discovery stn 11540, 2. IX. 1987, 1 spm (BMNH).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E4BFFB507D0FA3FB544CA5E.taxon	distribution	DISTRIBUTION. — Only known from the Cape Verde Basin.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E4BFFB507D0FA3FB544CA5E.taxon	description	DESCRIPTION Shell to 29 mm long, rather solid, variable in outline and sculpture, subcircular (length / height ratio between 1.1 and 1.2), compressed. Anterior margin rather narrowly rounded, posterior margin more or less conspicuously truncated, occasionally slightly sinuous, with rounded corners. Ventral margin convex, nearly semi-circular. Beaks just in front of the vertical midline. Exterior with numerous, very fine, irregular growth lines and commarginal lamellae which in juvenile specimens are very close-set and evenly spaced, in adult and subadult specimens they are more irregularly and wider spaced, obsolete or entirely missing. Earlier part of the valves often eroded. Posterior area delimited by gently rounded posterior angle, anterior angle absent. Lunule sunken, with rather thick layer of periostracum on it. Escutcheon long and very narrow, ligament slightly sunken. Hinge plate moderately broad, with two well developed cardinal teeth in each valve; posterior cardinal in the left valve rather thin and laminar. Laterals more or less indistinct. Diverging part of anterior adductor scar long. Inner margin smooth. Valves white. Periostracum very strong, yellowish brown, on the earliest parts of the valve thinner to obsolete. Measurements are provided in Table 7. BIOTOPE In soft sediment, most probably mud, found between 2003 and 2160 m.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E4BFFB507D0FA3FB544CA5E.taxon	discussion	REMARKS Lucinoma atalantae n. sp. is distinguished from L. vestita, the most similar species, by its larger size, the thinner and slightly longer valves, the narrower hinge plate and the sculpture. Lucinoma atalantae n. sp. shows dense commarginal lamellae on the earlier part of the valve whereas L. vestita is smooth. Juveniles of L. atalantae n. sp. are closer in outline to L. vestita but the narrower hinge line and the presence of commarginal lamellae remain distinguishing features. Both species have a different depth preference: L. vestita on the shelf slope at about 600 m, L. atalantae n. sp. much deeper, at about 2000 m. The two species have been taken at their type localities only, and we do not know their actual distribution range. Apart from an Indo-West Pacific species (under description by Cosel & Bouchet) which was found at 2570 m, L. atalantae n. sp. is the deepest-recorded lucinid species.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E49FFB30420FB9BB5CECBF2.taxon	description	(Figs 17; 18 A)	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E49FFB30420FB9BB5CECBF2.taxon	materials_examined	TYPE MATERIAL. — Holotype: N Angola, Angola margin, W of Ambrizete, 7 ° 18.42 ’ S, 12 ° 04.60 ’ E, 360 - 367 m, BIOZAIRE Program site ZB-B, trawled RV Thalassa, ZAIANGO BIOL 2, stn CP 09, 29. VIII. 2000, leg. R. von Cosel, a complete shell (MNHN). Paratypes: same locality, 1 rv., 3 lv. (MNHN); 1 rv., 1 lv. (BMNH). TYPE LOCALITY. — Ambrizete, Northern Angola, tropical West Africa.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E49FFB30420FB9BB5CECBF2.taxon	etymology	ETYMOLOGY. — Dedicated to my collegue Myriam Sibuet, principal investigator of the ZAIANGO BIOL and BIOZAIRE program and cruise leader of ZAIANGO BIOL 2, in which the author participated and in which the species was taken. OTHER MATERIAL EXAMINED. — Nigeria. S of Port Harcourt, 3 ° 42.28 ’ N, 7 ° 47.59 ’ W, 425 m, taken by corer, RV Le Suroît, GUINESS 2, stn KG 2 N 11, 2. IX. 1993, leg. P. Cochonat, 1 sh. with “ fossilized ” hardened mud between valves (MNHN).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E49FFB30420FB9BB5CECBF2.taxon	materials_examined	Gabon. SW of Port-Gentil, 1 ° 35.60 ’ S, 8 ° 34.69 ’ E, 410 m, boxcorer, RV Le Suroît, GUINESS 2, stn GGS 2 G 10, 25. VIII. 1993, leg. P. Cochonat, 1 lv. (MNHN). Northern Angola. W of Ambrizete, 7 ° 18.42 ’ S, 12 ° 04.60 ’ E, 360 - 367 m, trawled RV Thalassa, ZAIANGO BIOL 2, stn CP 09, 29. VIII. 2000, leg. R. von Cosel, associated specimens: numerous rv. and lv. in part more or less worn (MNHN). — W of Ambrizete, 7 ° 18.38 ’ S, 12 ° 04.72 ’ E, 363 m, taken by boxcorer, RV Thalassa, ZAIANGO BIOL 2, stn KGS 20, 29. VIII. 2000, leg. R. von Cosel, 1 juv. lv. (MNHN). — Same locality, 7 ° 18.31 ’ S, 12 ° 04.82 ’ E, 371 - 375 m, taken by ROV Victor, RV Atalante, BIOZAIRE 1, stn PL 79 - 3, 6. I. 2001, leg. M. Sibuet, 1 sh. (MNHN). DISTRIBUTION. — Gulf of Guinea: Nigeria to northern Angola. DESCRIPTION Shell to about 53 mm long, thick and solid, somewhat variable in outline, subcircular-triangular (length / height ratio mostly 1.1), rather inflated. Anterior part tapering, anterior margin narrowly and obliquely truncated, antero-ventral margin almost straight to straight. Posterior margin broadly rounded-truncated, with rounded corners. Ventral margin convex, more so in the middle than antero- and postero-ventrally. Antero-dorsal (lunular) margin straight to slightly concave, postero-dorsal margin convex. Beaks in front of the vertical midline. Exterior with strong, rather regularly and widely spaced commarginal lamellae which on the earlier parts of the valves are finer and closer-set and which are obsolete on the anterior area. Interspaces with numerous, densely spaced, somewhat irregular commarginal cords, becoming obsolete on the very early parts of the valves which may be eroded. Anterior area delimited by a rounded anterior angle, posterior area by a rounded and indistinct posterior angle. Lunule rather long and broad, sunken, with rather thick layer of periostracum on it. Escutcheon long and very narrow, delimited by a sharp keel, ligament sunken. Hinge plate strong, moderately broad, with two well developed cardinals in each valve; posterior cardinal in the left valve thinner than the others. Anterior and posterior lateral in the right valve present as strong and well distinct knobs. Left valve with two strong anterior laterals and one weaker posterior lateral. Diverging part of the anterior adductor scar long and narrow. Inner margin smooth but ventral part of the inner surface, especially between mantle line and margin, with strong radial undulations. Valves whitish in life, periostracum rather thin and dirty brownish. Measurements are provided in Table 8. BIOTOPE No live specimens found. On sticky mud near mounds of Lophelia pertusa near reducing sediments (for details see Graecina karinae n. gen., n. sp.), shells and valves found between 360 - 425 m. REMARKS Two “ morphs ” of this variable species can be distinguished: the morph on which the type lot is based (Figs 17; 18 A), with rounded-triangular outline, and another, higher and more rounded morph with more dense commarginal sculpture (Figs 18 B; 19), which is covered separately in the next entry. All kinds of intergrades occur between these two morphs, therefore, there is no separation on species level.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E4FFFB10420FA3FB3EBCBF2.taxon	description	(Figs 18 B; 19)	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E4FFFB10420FA3FB3EBCBF2.taxon	materials_examined	MATERIAL EXAMINED. — Northern Angola. W of Ambrizete, 7 ° 18.42 ’ S, 12 ° 04.60 ’ E, 360 - 367 m, trawled RV Thalassa, ZAIANGO BIOL 2, stn CP 09, 29. VIII. 2000, leg. R. von Cosel, 3 sh., numerous rv. and lv. in part more or less worn (MNHN). — W of Ambrizete, 7 ° 18.31 ’ S, 12 ° 04.82 ’ E, 371 - 375 m, taken by ROV Victor, RV Atalante, BIOZAIRE 1, stn PL 79 - 3, 6. I. 2001, leg. M. Sibuet, 1 sh., several v. and fragments, more or less worn (MNHN). — Same locality, 7 ° 17.78 ’ S, 12 ° 02.66 ’ E, 372 - 408 m, taken by ROV Victor, RV Atalante, BIOZAIRE 1, stn PL 77 - 1, 5. I. 2001, leg. M. Sibuet, several mostly worn v. (MNHN).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E4FFFB10420FA3FB3EBCBF2.taxon	description	DESCRIPTION Shell to 53 mm long, thick and solid, variable in outline, subcircular (length / height ratio between 1.0 and 1.2), inflated. Anterior margin broadly rounded, with an indistinct truncation, antero-ventral margin almost more or less rounded. Posterior margin broadly rounded-truncated, with rounded corners. Ventral margin well convex. Antero-dorsal (lunular) margin straight to slightly concave, postero-dorsal margin convex. Beaks slightly in front of the vertical midline. Exterior with rather densely to more widely spaced commarginal lamellae and on the interspaces with numerous, strong and dense, more or less irregular commarginal cords, becoming obsolete on the very early parts of the valves which may be eroded. Anterior area delimited by a rounded anterior angle, posterior area by a rounded posterior angle and often marked by a shallow to indistinct indentation of the posterior margin. Lunule and hinge dentition as in the “ normal ” morph. Measurements are provided in Table 9.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E4FFFB10420FA3FB3EBCBF2.taxon	discussion	REMARKS This “ morph ” is distinguished from the type series by its shorter, higher and more rounded shells with much denser commarginal lamellae. The shells are often more tumid. There are all kinds of intermediates to the “ normal morph ”. Lucinoma myriamae n. sp. with its two morphs shows well the plasticity of species of Lucinoma at a single locality. The nominate “ morph ” could be compared with Lucinoma species from the Indo-West Pacific of which one (under description by Cosel & Bouchet, unpubl. data) has the same outline and ornamentation. A close-looking species is Lucinoma kazani Salas & Woodside, 2002, found live in the eastern Mediterranean in a cold seep area on mud volcanoes in the Anaximander Mountains at 1165 - 1854 m depth S of Turkey (Salas & Woodside 2002). However, L. kazani is smaller (up to 38.4 mm length), less high and has finer commarginal cords, also with strong and irregular growth lines between them (see Fig. 18 C). The diverging part of the anterior adductor scar is somewhat broader and shorter as in L. kazani. The other large Atlantic species, L. borealis (Linnaeus, 1767) (northern Norway to Cap Blanc, Mauritania and throughout the Mediterranean), is more circular, slightly smaller (on the West African coast to a length of 40 mm), in average less tumid and, in contrast to L. myriamae n. sp., it has more densely spaced irregular commarginal ridges or lamellae. An interesting fact is the similar distribution patterns of the cold seep species pairs Lucinoma kazani - L. myriamae n. sp. and Isorropodon perplexum - I. bigoti (Vesicomyidae, see Cosel & Salas 2001), of which one species lives on the seeps in the eastern Mediterranean and the other species off northern Angola.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E4DFFB107E1FA3FB223C8F7.taxon	materials_examined	TYPE SPECIES. — Anodontia alba Link, 1807, by original designation. SPECIES INCLUDED. — 25 species (Taylor & Glover 2005), worldwide.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E4DFFB107E1FA3FB223C8F7.taxon	diagnosis	DIAGNOSIS. — Shells small to very large, equivalve, inequilateral, very tumid to globose, thin to moderately thick, circular to subcircular, with more or less protruding umbones. Hinge plate very narrow, toothless, ligament plate horizontal to shell margin or slanting towards the interior of the valve. Surface smooth, with more or less pronounced irregular growth lines and stages. Anterior adductor scar small, with comparatively short and small diverging part.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E4DFFB107E1FA3FB223C8F7.taxon	discussion	REMARKS A detailed worldwide revision of the genus has recently been published by Taylor & Glover (2005). The subgeneric classification followed here is also treated therein.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E72FF8D0784F99DB1ACC8F0.taxon	description	(Figs 20; 21 A, B)	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E72FF8D0784F99DB1ACC8F0.taxon	materials_examined	TYPE MATERIAL. — Holotype: Gabon, Port-Gentil, Banc du Prince, 0 ° 36.1 ’ S, 8 ° 48.1 ’ E, 5 - 9 m, a complete shell (MNHN). Paratypes: same locality, 1980 - 1989, leg. C. Chevalier, 3 sh. (MNHN); 1 sh. (BMNH 20040252). TYPE LOCALITY. — Port-Gentil, Banc du Prince, a shoal ENE of Cap Lopez, Mandji Peninsula, Gabon. OTHER MATERIAL EXAMINED. — Côte d’Ivoire. Continental shelf in Abidjan region (no details), trawled RV Reine Pokou, 1975 - 1977, leg. P. Le Loeuff, 4 sh., 1 juv. sh., 1 lv. (MNHN). Benin. Ouidah [Wydah], 6 ° 10 ’ N, 2 ° 05 ’ E, 200 m, dredged RV Léon Coursin, leg I. Marche-Marchad, 1 rv. (MNHN). — 6 ° 05 ’ N, 2 ° 15 ’ E, 180 - 320 m, trawled RV Thierry, Guinean Trawling Survey, stn 35 / 7, leg. G. Cherbonnier, 4. X. 1963, 1 rv., 2 lv. (MNHN). Gabon. Port-Gentil, Banc du Prince, 0 ° 36.1 ’ S, 8 ° 48.1 ’ E, 5 - 9 m, 1980 - 1989, leg. C. Chevalier, 7 associated specimens (sh.) (MNHN).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E72FF8D0784F99DB1ACC8F0.taxon	distribution	DISTRIBUTION. — Only known from Côte d’Ivoire, Bénin and Gabon.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E72FF8D0784F99DB1ACC8F0.taxon	description	DESCRIPTION Shell to 42 mm long, rather thin but solid, equivalve, inequilateral, very inflated, quite-variable in outline, more or less longer than high, subcircular to short-ovoid, length / height ratio 1.1. Umbones prominent, well protruding over the dorsal margin, directed forward, beaks well in front of the vertical midline. Anterior part short, anterior margin with a rather broadly rounded antero-dorsal corner, towards ventrally convex. Ventral margin well rounded and evenly convex. Posterior part broad, posterior margin well rounded, postero-dorsal corner indistinct, no postero-ventral corner. Exterior without regular sculpture and only with coarse and very irregular growth lines and wrinkles and more pronounced growth stages. A few shallow, very broad and indistinct radial waves are also visible, especially under certain angle of view. Anterior and posterior angle absent. Lunule small and short, more or less narrow, almost symmetric, not sunken; escutcheon absent. Ligament moderately long, broad, partly hidden by the postero-dorsal margin but not very deep sunken, on a broad nymph, which is obliquely, nearly “ vertically ” tilted towards the interior of the valves; therefore ligament and hinge plate appearing narrow at a horizontal view of the valve inside, full width of the ligament only visible from ventrally. In smaller specimens, ligament may be less broad. Hinge plate very narrow and toothless. Anterior adductor scar small, with a rather narrow diverging part, the pallial line meeting the scar above its middle, occasionally at one third the length of the scar. Posterior adductor scar very small. Anterior, ventral and posterior margin on the inner side slightly, irregularly and very finely dentate, but on the very edge smooth. Valves pure white. Periostracum very thin, pale straw coloured and mostly eroded. Measurements are provided in Table 10. BIOTOPE In muddy-sandy bottom on the deeper shelf, apparently only in the Port-Gentil region of Gabon occurring shallower, from about 5 m downwards. REMARKS This species is characterized by its very inflated shell, the broad ligamental nymph which is slanting towards the interior of the valve and the slightly dentate inner margin. A similar and possibly sibling species is Anodontia eutornus (Tomlin, 1921) from the Indian Ocean coast of South Africa, SE Africa and SE Madagascar, described as Cryptodon eutornus by Tomlin (1921: 215, pl. 8, fig. 5). It has the same typical ovoid shell form and exceptional tumidity as Anodontia chevalieri but is still larger. Although that species had been well recognized by Barnard (1950: 181, pl. 28, fig. 5) with a figure of a typical specimen, in more recent works on South African molluscs, it was always mistaken for or synonymized with A. edentula (Linnaeus, 1758) (Barnard 1964; Kilburn & Rippey 1982; Steyn & Lussi 1998). This is additional evidence for the close affinity of the West African marine molluscan fauna with the Indo-Pacific, especially with the Indian Ocean. For further details, see Taylor & Glover (2005).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E71FF8B05CDFA98B0BBC851.taxon	description	(Figs 21 C, D; 22)	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E71FF8B05CDFA98B0BBC851.taxon	materials_examined	TYPE MATERIAL. — Holotype: Senegal, S of Gorée, 110 - 112 m, lv., dredged RV Gérard Tréca, leg I. Marche-Marchad, 18. II. 1954 (MNHN). Paratypes: Dakar region, 14 ° 50.2 ’ N, 17 ° 29.5 ’ W, 150 m, dredged RV Tenace, 15. III. 1967, leg. I. Marche-Marchad, 2 rv. (MNHN); 1 lv. (BMNH 20040238). TYPE LOCALITY. — Dakar, Senegal. MATERIAL EXAMINED. — Mauritania. Off Cap Blanc, 20 ° 34 ’ N, 17 ° 47 ’ W, 90 m, trawled RV Président Théodore Tissier, 1936, 2 rv., 6 lv. (MNHN). Senegal. Dakar region, 14 ° 53.8 ’ N, 17 ° 30.8 ’ W, 205 - 230 m, dredged RV Gérard Tréca, 18. III. 1958, leg I. Marche-Marchad, 4 rv., 3 lv. (MNHN). — S of Gorée, 65 m, dredged RV Gérard Tréca, 18. II. 1954, leg I. Marche-Marchad, 1 rv. (MNHN). — Baie de Gorée, 125 - 160 m, dredged RV Gérard Tréca, 14. II. 1958, leg. I. Marche-Marchad, 1 juv. lv. (MNHN). — Dakar region (no precision), 129 - 150 m, dredged RV GérardTréca, 24. I. 1958, leg. I. Marche-Marchad, 1 rv. (MNHN). — Dakar region (without any precision), leg. I. Marche-Marchad, 1 chipped rv. (MNHN).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E71FF8B05CDFA98B0BBC851.taxon	distribution	DISTRIBUTION. — Off Mauritania (20 ° 30 ’ N) and Senegal.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E71FF8B05CDFA98B0BBC851.taxon	description	DESCRIPTION Shell to 37 mm long, thin but solid, equivalve, inequilateral, very inflated, variable in outline, subcircular, somewhat longer than high, length / height ratio 1.1 - 1.2. Umbones prominent, well protruding over the dorsal margin, directed forward, beaks in front of the vertical midline. Anterior part short, anterior margin with a broadly rounded antero-dorsal corner, towards ventrally convex. Ventral margin well rounded and evenly convex. Posterior part broad, posterior margin well rounded, postero-dorsal corner indistinct, no postero-ventral corner. Exterior without regular sculpture and only with fine, irregular growth lines and coarser growth stages. A few very shallow and almost indistinct radial waves may be visible on large specimens, especially under a lens at certain angle of view. Anterior and posterior angle absent. Lunule very small and short, rather narrow, almost symmetric, not sunken; escutcheon absent. Ligament moderately long, not sunken, on a narrow nymph, which is slanting towards the interior of the valves; therefore ligament and hinge plate appearing still narrower at a horizontal view of the valve inside, full width of the ligament only visible from ventrally. Hinge plate very narrow and toothless. Anterior adductor scar with a short and rather broad diverging part, the pallial line meeting the scar above its middle, occasionally at almost one third the length of the scar. Posterior adductor scar very small. Anterior, ventral and posterior margin on the inner side almost smooth, occasionally the vestiges of inner crenulations are visible. Valves white, periostracum not observed. Measurements are provided in Table 11. BIOTOPE Most probably muddy bottom, on the deeper shelf between about 60 and 230 m.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E71FF8B05CDFA98B0BBC851.taxon	discussion	REMARKS This species is distinguished from Anodontia chevalieri by the smaller size, the shorter and broader diverging part of the anterior adductor scar and the narrower and shallower ligament, which is less slanting towards the interior of the valves. The inner margin is smooth (see also Taylor & Glover 2005).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E77FF880638F99EB30CCA9C.taxon	materials_examined	TYPE AND ONLY SPECIES. — Joellina dosiniformis n. sp.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E77FF880638F99EB30CCA9C.taxon	distribution	DISTRIBUTION. — Off Ambrizete, northern Angola, tropical West Africa.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E77FF880638F99EB30CCA9C.taxon	diagnosis	DIAGNOSIS. — Shells medium-sized, subcircular, slightly oblique towards posterior, hardly longer than high to almost as long as high, compressed, with a rather short and broad anterior part and a high, broad and oblique posterior part, without indentation. Anterior margin rounded and in its upper part slightly indented. Beaks well in front of the vertical midline. Umbones slightly prominent. Surface with irregular commarginal lamellae and growth lines. Antero-dorsal depression short and pronounced, postero-dorsal depression broad and illdefined. Lunule very short, narrow, asymmetrical and deeply sunken, escutcheon very narrow and completely filled by the ligament. Hinge plate very broad with long posterior part, with one very small and vestigial cardinal in the right valve and socket in the left valve; laterals small to indistinct. Ligament short and broad. Diverging part of anterior adductor scar long and broad, with a length of about 2 / 3 the total length of the scar. Inner margins smooth.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E77FF880638F99EB30CCA9C.taxon	etymology	ETYMOLOGY. — Dedicated to my colleague Joëlle Galeron (IFREMER, Brest) in acknowledgement for her close collaboration on the deep-water mollusc fauna.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E77FF880638F99EB30CCA9C.taxon	discussion	REMARKS This new genus is most close to the fossil genus Pterolucina Chavan, 1942, from the Upper Cretaceous to Tertiary (Miocene) (type species Lucina coeloprocta Cossmann, 1887, Upper Eocene of France), there is no Recent lucinid genus with which it can be compared, however, according to the description and figure in Chavan (1969), Pterolucina has more separated areas and a stronger hinge dentition.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E74FF8607D2FAD8B092CADC.taxon	description	(Figs 23; 24)	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E74FF8607D2FAD8B092CADC.taxon	materials_examined	TYPE MATERIAL. — Holotype: N Angola, Angola margin, W of Ambrizete, 7 ° 18.42 ’ S, 12 ° 04.60 ’ E, 360 - 367 m, trawled RV Thalassa, ZAIANGO BIOL 2, stn CP 09, 29. VIII. 2000, leg. R. von Cosel, right valve (MNHN). Paratypes: same locality, 1 rv., 3 lv. (MNHN); 1 rv. (BMNH). TYPE LOCALITY. — Ambrizete, Northern Angola, tropical West Africa.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E74FF8607D2FAD8B092CADC.taxon	etymology	ETYMOLOGY. — The name characterizes the shell outline reminiscent of a Dosinia.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E74FF8607D2FAD8B092CADC.taxon	distribution	DISTRIBUTION. — Only known from the type locality.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E74FF8607D2FAD8B092CADC.taxon	description	DESCRIPTION Shell to 32 mm long, somewhat variable in outline, rather thick and solid, equivalve, compressed, subcircular, oblique towards posterior, hardly longer than high to almost as long as high, length / height ratio 1.0 - 1.1. Umbones not prominent and hardly protruding, directed forward, beaks well in front of the vertical midline. Anterior part short and broad, anterior margin in its upper part almost straight to hardly indented, with a rather broadly rounded antero-dorsal corner to the lunular area. Ventral margin well rounded and evenly convex. Posterior part broad and high, posterior margin obliquely truncated, postero-dorsal corner protruding towards posterior, rounded but pronounced, postero-ventral corner broadly rounded and more indistinct. Exterior with irregularly and rather widelyspaced commarginal lamellae and dense and very irregular growth lines and wrinkles and coarser growth stages. Anterior angle almost absent, anterior radial depression sharply cut in, irregular, otherwise antero-dorsal area ill-defined. Posterior angle rounded, posterior radial depression broad and ill-defined. Lunule small and very short, narrow, asymmetric, deeply sunken; escutcheon very narrow, entirely filled by the ligament and delimited by a sharp keel. Ligament short, broad and deeply sunken. Hinge plate broad, strong, with long posterior part. Hinge in the right valve with a very small single cardinal which may be reduced to a rudimentary knob and a small but well marked anterior lateral. Left valve with a socket for the cardinal knob of the right valve and the vestiges of anterior and posterior laterals. Anterior adductor scar large with long and broad diverging part, the pallial line meeting the scar two thirds above its middle or slightly less. Posterior adductor scar rather large. Inner margin smooth. Valves presumably white in life but the dead collected samples are light greyish. Periostracum thin, greenish brown, when still present. Measurements are provided in Table 12. BIOTOPE As for Graecina karinae n. gen., n. sp. Only single valves taken.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E74FF8607D2FAD8B092CADC.taxon	discussion	REMARKS As for the genus. This species is characterized by the strong resemblance of its outline to certain species of the venerid genus Dosinia Scopoli, 1777 with high posterior part (e. g., Dosinia erythrea (Römer, 1860 )) and also the large hinge plate and the anteriorly placed, non-protruding umbones add to this resemblance. No other lucinid is known to have this combination of characters.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E7AFF85078DFAF8B0DEC8F0.taxon	materials_examined	TYPE MATERIAL. — Holotype: Gabon, Port-Gentil, Île aux Pigeons, 0 ° 40.5 ’ S, 8 ° 45.3 ’ E, muddy sand near mangroves, 1980 - 1989, leg. C. Chevalier, 1 sh. (MNHN). Paratypes: same locality, 8 sh. (5 MNHN, 1 BMNH, 1 IRSNB, 1 ZMC).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E7AFF85078DFAF8B0DEC8F0.taxon	description	D. dentata var. collignoni: type lot in Chavan collection (holotype, rv., Îles Glorieuses, coll. Chavan no. 1223; paratype, a sh., Corisco, coll. Chavan no. 668); the Chavan collection is now in University Lyon 1.	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
666D24433E7AFF85078DFAF8B0DEC8F0.taxon	materials_examined	TYPE LOCALITY. — Île aux Pigeons, Port-Gentil, Gabon. ETYMOLOGY. — In honour of André Chavan, who had made the first attempt to revise the Divaricella group. OTHER MATERIAL EXAMINED. — Senegal. Cap Vert Peninsula, coll. de Cessac, 1 lv. (MNHN). — Off Saloum, Petite Côte, 35 - 37 m, dredged RV Gérard Tréca, 8. III. 1955, leg. I. Marche-Marchad, 1 lv. (MNHN). — Casamance, 12 ° 46.9 ’ N, 17 ° 29.9 ’ W, 45 m, fine sand, dredged RV Louis Sauger, 29. III. 1988, leg. R. von Cosel, 1 juv. lv. (MNHN). — Senegal (no precision), coll. Admiral de Hell, 1846, 1 sh. (MNHN). Côte d’Ivoire. Abidjan region (no precision), leg. I. Marche-Marchad, 1 rv., 1 lv. (MNHN). Gabon. Île Banié, southern part of Golfo de Corisco, sand, 3 - 6 m, 1986 - 1987, leg. P. Bernard, 2 sh. (MNHN). — Cap Esterias, Libreville, 1 - 4 m, 1986 - 1987, leg. P. Bernard, 2 rv. (MNHN). — Port-Gentil, sand, 2 - 5 m, 1986 - 1987, leg. P. Bernard, several v. (MNHN). — Port- Gentil, Plage de la Sogara, beach drift, 12. I. 2004, leg. R. von Cosel, 1 sh., several v. (MNHN). — Gabon (no precision), 1853, coll. Aubry Lecomte, 2 sh., 1 rv. (MNHN). — 0 ° 38.4 ’ S, 8 ° 46 ’ E, sand with forams, 5 m, dredged RV Calypso, 10. VI. 1956, leg. I. Marche-Marchad, 1 juv. rv. (MNHN). Congo (Brazzaville). Pointe-Noire, Plage Mondaine, beach drift, XII. 1985, leg. R. von Cosel, 1 rv. (MNHN). DISTRIBUTION. — Mauritania (Quaternary only, [Cou- lombel 1980]), Senegal (Saloum to Casamance); Sierra Leone (Sherbro), Côte d’Ivoire to the Congo (Pointe- Noire). There are no records from Guinea-Bissau to Liberia and a distribution gap is very probable. The species is common in Gabon and rare elsewhere. DESCRIPTION Shell 15 - 28 mm long, rather solid, inflated, almost circular, length / height ratio 1.1. Beaks about in the middle. Antero-dorsal margin divided into two slightly concave to almost straight parts with a rounded corner between them and another rounded corner to the anterior margin. Posterodorsal margin slightly convex, postero-dorsal corner more or less rounded, posterior margin somewhat truncated, ventral margin evenly and well rounded. Exterior with fine, regular, dense, contiguous, divaricate ribs, with the line of sharp, V-shaped divarication going from the beaks to the anteroventral margin. Sculpture more marked near the anterior and posterior margin than in the middle of the valve. Anterior area small, posterior area not distinguished. Hinge in the right valve with a small, more or less pronounced anterior cardinal and a broad and bifid posterior cardinal. Left valve with a strong but rather thin anterior and a thin posterior cardinal. Both valves with an indistinct knob as anterior lateral under the distal end of the lunule, posterior lateral a small knob under the postero-dorsal corner. Lunule very small and short, somewhat sunken, asymmetrical, broad in the right valve, narrow in the left valve, no escutcheon. Ligament deeply sunken and only partly visible from the exterior at dorsal view. Anterior adductor scar with moderately long extension separate from the pallial line, this latter meeting the impression at the end of the upper third. Inner margin crenulate in reflection of the external sculpture. Valves entirely white, periostracum not seen. Measurements are provided in Table 13. BIOTOPE Sandy bottom, mostly in shallow water (1 - 6 m) but apparently also deeper. REMARKS This species was long known as Lucina ornata Reeve, 1850, but this name is preoccupied by Agassiz, 1845. Chavan (1951) considered his material from West Africa and from East Africa conspecific with the Caribbean Divaricella dentata (Wood, 1815) (syn. D. serrata (d’Orbigny, 1846 )), but he separated them as a “ nov. var. ”, Divaricella (Egracina) dentata var. collignoni. Moreover, Chavan designated this variety in the same entry as type species of his new subgenus Egracina. Chavan’s type lot, however, as he admits himself (“ forme africaine du dentataserrata des Antilles ”) is a mixed lot: it consists of a specimen from West Africa (“ Corisco ”) and a specimen of a close western Indian Ocean (“ Îles Glorieuses ”) species which in his figure legend he designated explicitly as holotype (Chavan 1951: 21), the West African species being the paratype. Chavan’s name is hence not available for the West African species. Reeve’s type lot in BMNH (no locality) consists of two syntypes (single valves) from which the right valve was selected lectotype by Dekker & Goud (1994). This valve has a more sloping postero-dorsal margin than most specimens from West Africa but it still might fall within the variability of the West African species. The other (left) valve has a stronger sculpture and is more likely to belong to another species. Moreover, Dekker & Goud (1994) synonymized D. ornata (Reeve, 1850) with D. irpex E. A. Smith, 1885, a totally different Australian species. To avoid confusion, the West African species is here described as new, and the holotype is taken from “ modern ” and well localized material. The distribution pattern of this species is still somewhat enigmatic: it is rare in the southern (weaker) part of the northern zone of Alternance (Senegal: Petite Côte, Casamance, see Le Loeuff & Cosel 1998), it is absent from the northern typical tropical zone (Guinea-Liberia), and it is rare in the atypical tropical zone in the Gulf of Guinea (Côte d’Ivoire). It has not been recorded from Cameroon, however, on the coast of Gabon situated in the southern part of the southern typical tropical zone it is common; whereas in the weaker part of the southern zone of Alternance (Congo) it is present but rarer. Moreover, in the southern part of its range the species lives in quite shallow (1 - 6 m), whereas the few records from Senegal are from deeper water (35 - 45 m).	en	Cosel, Rudo von (2006): Taxonomy of tropical West African bivalves. VI. Remarks on Lucinidae (Mollusca, Bivalvia), with description of six new genera and eight new species. Zoosystema 28 (4): 805-851, DOI: 10.5281/zenodo.4689802
