Opisthostoma megalomphalum van Benthem Jutting, 1952

Morphology: 

By Benthem Jutting (1952)

"shell short-cyclindrical, white. First whorl smooth, following ones ornamented with fine white transverse ribs, closely placed in the upper whorls, but wider apart on the last one. Not shinning or transparent. No spiral striation visible. Whorls 4, convex. Top whorl placed oblique on the axis of the shell. First two whorls lying in one plane, hence the top of the shell is flat. Last whorl somewhat transversely constricted in the middle, then widening again, making at the same time a sharp twist upward so that the aperture faces the sky. Suture deep. umbilicus wide. Aperture adnate, round. Peristome continuous, circular or rounded-triangular, duplex. Reaching somewhat over halfway up the height of the penultimate whorl. Operculum unknown."

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith