Axinus subovatus Jeffreys, 1881
Axinulus subovatus ( Jeffreys, 1881 )
Leptaxinus ( L. ) subovatus (Jeffreys)
Thyasira ( Parathyasira ) subovata subovata ( Jeffreys, 1881 )
Thyasira ( Parathyasira ) subovata minuta Payne & Allen 1991
Thyasira ( Parathyasira ) subovata ( Jeffreys, 1881 )
Thyasira subovata Jeffreys, 1881
Leptaxinus subovatus ( Jeffreys, 1881 )
Bathyal Mollusca from the cold-water coral biotope of Santa Maria di Leuca (Apulian margin, southern Italy)
Negri, Mauro Pietro
Corselli, Cesare
Zootaxa
2016
4186
1
1
97
Jeffreys, 1881
Jeffreys
1881
[151,611,152,178]
Bivalvia
Thyasiridae
Leptaxinus
Animalia
Lucinoida
35
36
Mollusca
species
subovatus
Axinus subovatus Jeffreys, 1881(p. 704, pl. 61, fig. 8). Axinulus subovatus( Jeffreys, 1881)— Nordsieck 1969(p. 80, pl. 13, fig. 48.13). Leptaxinus( L.) subovatus(Jeffreys)— Di Geronimo 1974(p. 156, pl. 3, fig. 2). Thyasira( Parathyasira) subovata subovata( Jeffreys, 1881)— Payne & Allen 1991(p. 513, figs. 48–50, 53 a–b). Thyasira( Parathyasira) subovata minuta Payne & Allen 1991(p. 515, figs. 51–52, 53 c–d). Thyasira( Parathyasira) subovata( Jeffreys, 1881)— Giribet & Peñas 1997(fig. 100). Thyasira subovata Jeffreys, 1881— Oliver et al.2002(p. 60, pl. 25, figs. A–B). Leptaxinus subovatus( Jeffreys, 1881)— Repetto et al.2005(p. 310, bottom right fig.). Diagnostic characters. Oval, oblique shell; long anterior side; roundly angular posterior side; outer surface with uneven and rather coarse growth markings; right valve hinge with 1 cardinal tubercle and 2 lamellar lateral teeth; left valve hinge with 1 cardinal tubercle. Prodissoconch: shell type ST-2D; length about 120 µm; roundish Dshaped outline; low convex profile; surface smooth; P-2 absent; transition to the nepioconch poorly marked.
Remarks. The specimens at hand appear to be more similar to the subspecies minuta Payne & Allen, 1991, than to the nominal species of Jeffreys, in having an oval (not subtriangular) shell with rounded (not wedgeshaped) posterior angulation. We follow Oliver & Levin (2006)in preferring the genus Leptaxinus Verrill & Bush, 1898for the present taxon, rather than ThyasiraLamarck, 1818, for the presence of both cardinal tubercles and lateral teeth. Occurrence. Box-corer samples BC10 (2 specimens), BC66 (2), BC67 (3), BC72 (5); cores BC21 (1), BC72 (5). Maximum length: 2.5 mm.
Distribution and habitat. Leptaxinus subovatusis distributed troughout the Atlantic, from Icelandand Faroes to CapeVerde, Angolaand Argentina, and in the Mediterranean; it is found in the 200–4000 mbathymetric interval, reaching shallower depths at arctic latitudes ( Payne & Allen 1991; Poppe & Goto1993; Di Geronimo et al.2001; Sneli 2005). Fossil record.Pliocene of northern Italy ( Tabanelli 2008).