Microglyphis Dall, 1902

Helwerda, Renate A., 2015, Acteonidae, Bullinidae and Ringiculidae (Gastropoda: Heterobranchia) from the Plio-Pleistocene of the Philippines, Zootaxa 3990 (2), pp. 197-220 : 215

Genus Microglyphis Dall, 1902

Type species. Actaeon curtulus Dall, 1889 (by original designation); Recent, off Magellan Strait.

Remarks. Shells of this genus are similar to shells of the genus Ringicula , except that they do not develop a thickly callused aperture. This makes them difficult to distinguish from juvenile Ringicula shells, but they exhibit determinate growth characters subtly, such as a thin callus and a subtle change in coiling direction in the aperture. All adult shells of a Microglyphis species typically reach the same size as well. Burn & Thompson (1998) mention that Microglyphis shells have only one columellar fold, but, while this is the case in M. japonica ( Habe, 1952) , there are also species with two columellar folds, such as M. mazatlantica ( Dall, 1908) and M. estuarina ( Dall, 1908) .