Chersaecia shiroiensis (Godwin-Austen, 1875)

Diagnosis

Shell very small, last quarter of whorl keeled basally with a shallow groove between the suture and the keel; main parietal plica long, its posterior portion is much more elevated than the anterior, and bends downwards (in the direction of the lower suture).

Differential diagnosis

The shape of the last half/quarter whorl (groove and periumbilical keel) is characteristic for this species. See also under both subspecies.

Remarks

The two subspecies differ considerably in the parietal plication, but they are almost identical in outer shell characters, therefore they are handled as subspecies of a single species.