‘ Odostomia ’ s.l. sp. 2, J. Fleming, 1813

Thivaiou, Danae, Harzhauser, Mathias & Koskeridou, Efterpi, 2019, Early Miocene Gastropods from the Felli Section (Proto-Mediterranean Sea NW Greece), Geodiversitas 41 (8), pp. 323-366 : 350

‘ Odostomia ’ s.l. sp. 2

(Fig. 8 A1, A2)

MATERIAL EXAMINED. — Sample F11: AMPG ( IV) 2558, 2559 (two specimens).

DIMENSIONS. — Maximum height: 1.30 mm.

DISTRIBUTION. — Early Miocene. Proto-Mediterranean Sea: Greece (this paper).

DESCRIPTION

Type B planispiral and partially immersed protoconch. Teleoconch of three flat whorls; sculpture consists of inconspicuous orthocline growth lines; sutures impressed. Last whorl angular; umbilicus small and narrow, aperture oval, outer lip missing.

REMARKS

The shell is short and conical; all specimens have a type B protoconch with an arch-shaped suture ( Peñas & Rolán 2010). The apex of the protoconch forms a concavity to the suture between protoconch and first teleoconch whorl, which is a feature, observed in some specimens with type B partially immersed protoconchs in the genus Eulimastoma. Nevertheless, the present specimen lacks other characters that could place it in the latter genus (inflated suprasutural band, sculpture of the base of the shell).

Figures

FIG. 8. — A1, A2, ‘Odostomia’ sp. 2, AMPG(IV) 2558; B1-B3, Megastomia sp. 1, AMPG(IV) 2560; C1, C2, Brachystomia sp., AMPG(IV) 2570; D1-D3, Megastomia sp. 2: D1, AMPG(IV) 2563;D2, D3, AMPG(IV) 2564;E1-E4, Pyramistomia aliakmoni n. sp.: E1, E2, holotype, AMPG(IV) 1500;E3, paratype 1, AMPG(IV) 1501 (SEM image); E4, AMPG(IV) paratype 1, AMPG(IV) 1501, protoconch (SEM image); F1-F4, Parthenina sp. 1: F1, F2, AMPG(IV) 1573; F3, AMPG(IV) 1574 (SEM image); F4, AMPG(IV) 1574, apex (SEM image); G1, G2, Parthenina sp. 2: G1, AMPG(IV) 2575; G2, AMPG(IV) 2575, apex (SEM image); H,?Syrnola sp., AMPG(IV) 2577 (SEM image). Scale bars: A1, A2, B1-B3, D1, G1, H, 500 µm; C1, C2, D2, D3, E1, E2, 1 mm; E3, F1, F2, 400 µm; E4, F3, 200 µm; F4, G2, 100 µm.