Rodzaj Shurovites Guzhov, 2004
Gatunek typowy Opis Shell small, turriculate, with straight or convex generating line. Protoconch composed of 3.0 - 3.5 whorls. First 1.5 whorls rounded and smooth. Rounded angularity appearing on subsequent 1.5- 2.0 whorls initially observed in upper third of whorl and later descending to the middle. Carina formed in its place only in 0.4-0.7 whorl from protoconch end. Boundary between protoconch and teleoconch distinct, marked by opisthocyrt commissure and appearance of folds and strong ribs. Teleoconch whorls flattened or convex, nongradate or slightly gradate. Ornamentation composed of three or four primary ribs and few (0-2) secondary ribs. Folds cross secondary ribs, forming tubercles. Shell base high, convex, arched or widely conical, with numerous ribs and fold ends. Aperture circular or oval, with short groove in basal area. Differs from other members of the subfamily in the protoconch with several smooth rounded whorls and a single carina on the last whorl. Synonimy Zasięg czasowy Late Toarcian to Oxfordian. Literatura Guzhov, A. V. 2004. Jurassic gastropods of European Russia (Orders Cerithiiformes, Bucciniformes, and Epitoniiformes). Paleontological Journal, 38, Supplement 5, 457-562. |
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