Gatunek typowy
Cerithium (cf.) pommeranum Schmidt, 1905. Oxfordian, Kłęby, Poland.

Opis

Shell slender, large, with many whorls; protoconch heterostrophic, transaxial, distinctly emerged, detached or almost detached from initial teleoconch whorl; early teleoconch whorls with two strong and of ten several weakerspiral ribs as well as numerous opisthocyrt axial ribs; strong abapical spiral rib moves down towards the abapical suture until it is positioned slightly above the abapical suture; this spiral becomes stronger during ontogeny; at the same  time,strong adapical spiral is weakening and may fade entirely; below adapical suture one or two spiral ribs become increasingly stronger; whorl face straight to concave (in most species); axial ribs are reduced to strong growth lines on the last whorls of adult specimens.

Synonimy

Zasięg czasowy

Bajocian to the Oxfordian; Germany, France, Luxembourg, Poland and Russia.

Literatura

Gründel, J. 1990a. Gastropoden aus Callov−Geschieben aus dem Norden der DDR. I. Procerithiinae und Mathildidae. Zeitschrift für Geologische Wissenschaften 18, 763–773.