Cerithiella Verril, 1882

Hansen, Thomas, 2019, Gastropods from the Cretaceous-Palaeogene boundary in Denmark, Zootaxa 4654 (1), pp. 1-196 : 117

Genus Cerithiella Verril, 1882

Type species. Cerithium metula Lovén, 1846 (designation by Sars (1878) when erecting Lovenella Sars, 1878 , a name already in use). Recent, Europe.

Remarks. It was suggested by Nützel (1998) that all fossil taxa with a planktotroph multispiral protoconch may have to be assigned their own genus or reassigned to other genera as all extant species of Cerithiella are characterized by a lecithotroph larval shell. It is clear that the present definition of the genus is rather wide and it seems plausible that the planktotrophic taxa in general would be closer related to each other than to the lecithotrophic forms. I do not think that there is any basis for a higher taxonomical reassignment of the planktotrophic forms within the cerithiopsids, as was suggested on a tentative basis by Nützel (1998). Actually there are all grades of intermediates between the two groups and even within a single recent species like Cerithiella metula ( Lovén, 1846) as re-evalu- ated by Bouchet & Warén (1993) a surprisingly large variation in the protoconch morphology may be observed, depending on the environment or geographical location.