Diagnoza

The shell is broadly oval. The whorl grows faster in width than in height. The last whorl is very broad and it makes the whole shell outline slightly concave. The whorls of the spire are convex and the last whorl is inflated. There is a narrow ramp in the adapicalmost part of the whorls, with some angulation in the early whorls and a gradual change into the lateral flank in the last whorl. The shell is smooth apart from almost orthocline growth lines. The base is strongly convex, with a very small umbilical chink. The aperture is broadly oval.

Porównanie

Species of Amauropsis differ in having strongly prosocline growth lines, those of Ampullina differ in having an extremely expanded last whorl with a very short, mammillated spire, Oonia has no ramp, the growth lines are distinctly parasigmoidal and the inner lip forms a nearly straight line.

Autekologia

Występowanie geograficzne

Germany in Poland only in Kłęby (Western Pomerania); 

Zasięg czasowy

Late Jurassic; in Poland late Oxfordian

Materiały muzealne

Material from Germany and one complete and three damaged shells from Poland (BGR and Buchholz collections).

Literatura

Gründel, J & Kaim, A. 2006. Shallow-water gastropods from Late Oxfordian sands in Kłęby (Pomerania, Poland). Acta Geologica Polonica 56, 121‒157.

Quenstedt, F.A. 1858. Der Jura. 842 pp. Laupp & Siebeck, Tübingen.