Parthenina sp. 1, Bucquoy, Dautzenberg & Dollfus, 1883

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 : 354

Parthenina sp. 1

(Fig. 8 F1-F4)

MATERIAL EXAMINED. — Sample F11: AMPG ( IV) 2573, 2574 (two specimens).

DIMENSIONS. — Maximum height: 1.00 mm.

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

DESCRIPTION

Minute shell; type C protoconch. Two teleoconch spires preserved; axial sculpture consists of slightly sigmoidal and regularly spaced orthocline smooth ribs; spiral sculpture consists of flat spiral cords. Abapically, the cords overlap with the ribs. Aperture tear-shaped; strong columellar fold.

REMARKS

The sculpture and type C protoconch are similar to Chrysallida longula (Boettger, 1907) from the middle Miocene of the Paratethys and the Proto-Mediterranean ( Landau et al. 2013).

Parthenina longula (Boettger, 1907) differs from the Greek shell in its much more prominent axial ribs, the less convex first teleoconch whorl and the absence of the weak sutural cord. The weak sutural cord around the upper suture also allows a separation of this species from Parthenina amaciata (Nrusina, 1966), P. majae Landau, Harzhauser, İslamoğlu & Da Silva, 2013 and P. obtusa (Brown, 1827) as described by Landau et al. (2013) for the Serravallian (Middle Miocene) of Turkey. Furthermore, the sculpture of the shell is reminiscent of Parthenina belgica Glibert, 1958 (e.g. in Moths et al. 2010), with this species having a more elongated shell. It also differs from Parthenina pygmaea ( Grateloup, 1838) in having a finer spiral sculpture.

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.