Skeneidae indet., 1968

Albano, Paolo G., Steger, Jan, Bakker, Piet A. J., Bogi, Cesare, Bosnjak, Marija, Guy-Haim, Tamar, Huseyinoglu, Mehmet Fatih, LaFollette, Patrick I., Lubinevsky, Hadas, Mulas, Martina, Stockinger, Martina, Azzarone, Michele & Sabelli, Bruno, 2021, Numerous new records of tropical non-indigenous species in the Eastern Mediterranean highlight the challenges of their recognition and identification, ZooKeys 1010, pp. 1-95 : 1

Skeneidae indet. Figure 3

New records.

Israel • 1 sh; Akko; 32.92°N, 35.07°E; depth 4 m; 22 Oct. 1998; shell grit sample; size: H 0.6 mm, W 1.0 mm.

Remarks.

This tiny gastropod (largest diameter 1 mm) is characterized by a small but solid shell, ~ 0.75 whorls of protoconch with axial costae visible near the proto-teleoconch transition (more costae closer to the nucleus may be abraded), and two teleoconch whorls with numerous regular spiral cords. The shoulder is slightly angulated near the lip. Umbilicus open, large. Shell white, slightly translucent. No native Mediterranean species shares these features. Only Skenea catenoides (Monterosato, 1877) has a similarly solid shell with numerous regular spiral cords, but it can be distinguished easily by the three nodulose thicker spiral cords on the base and the lack of angulation at the shoulder. Both Mediterranean (e.g., Circulus striatus (Philippi, 1836) and Red Sea Circulus (e.g., C. novemcarinatus (Melvill, 1906a)) and C. octoliratus (Carpenter, 1856)) can be distinguished by the multispiral protoconch and the much more prominent spiral cords. It is most likely a new, probably still unnamed, Indo-Pacific species in the Mediterranean.

Figures

Figure 3. Skeneidae indet., Akko, Israel: apical (A, B), front (C, F), side (D, E), umbilical (G, H) and back (I) views, protoconch (J). Scale bars: 0.5 mm (A-I); 0.1 mm (J).