Tympanotonos sp.

Islamoğğlu, Yeşşim, Dominio, Stefano & Kowalke, Thorsten, 2011, Early Eocene Caenogastropods (Mollusca, Gastropoda) from Haymana-Polatl Basin, Central Anatolia (Turkey): taxonomy and palaeoecology, Geodiversitas 33 (2), pp. 303-330 : 320

Tympanotonos sp. ( Fig. 7A )

MATERIAL EXAMINED. — One specimen housed at the NHMV (2008z0310/0007).

LOCALITY AND HORIZON. — Grey siltstone, KIrkkavak Formation (Macunköy: sample G2).

DESCRIPTION

Medium-sized, turreted-conical shell, up to 27 mm high.Teloconch with more than seven slightly concave whorls with incised sutures. Four spiral ribs are visible. The adapical spiral is strongly developed, producing the shouldered outline of the shell. Early teleoconch whorls bear 12-16 axial ribs, which decrease in the course of the ontogeny to 10 on the body whorl. Nodes to short spines are formed in the points of intersection of the spiral and axial sculpture. Whorls moderately increase in width, resulting in an elongate turriculated outline of the shell; the aperture is narrow and quadrangular, siphonal channel slightly curved.

REMARKS

Tympanotonos sp. differs from T. turris by its more elongated shell, by bearing only four spirals and by the strongly developed axial sculpture.

Figures

FIG. 7. — Caenogastropods (deposited in the repositories of the Natural History Museum of Vienna and in the General Directorate of Mineral Research and Exploration, Ankara): A, Tympanotonos sp.; B,?Melanoides sp.; C, Terebralia sp. 1; D, Terebralia sp. 2; E, Vicinocerithium seni n. sp. (paratype-Vienna museum); F, Vicinocerithium seni n. sp. (paratype-MTA, Ankara); G, Vicinocerithium seni n. sp. (holotype-MTA, Ankara); H, “Cerithiid” indet.; I, Haustator granulosa (Deshayes, 1824); J, Haustator sp.; A-D, G, H, NHMV; E, F, I, J, MTA. Scale bars: 1 cm.