Taxon classification Animalia Mesogastropoda Diplommatinidae

Moussonia Semper, 1865

Moussonia Semper 1865, Journal de Conchyliologie, 13: 296. Type species: Pupa problematica Mousson, 1865, by original designation.

Diagnosis.

Shell elongate conical, dextral, oval, almost non-umbilicate; protoconch whorls smooth; teleoconch whorls usually with a blunt keel; whorls completely smooth to finely ribbed, sometimes with fine thread-like spirals; last whorl narrowed; columellaris ends as a tooth-like lamella in a central to basal position in the aperture; internal lamellar system with one columellaris, two parietal lamellae and one to two palatal lamellae. The operculum was not observed.

Remarks.

The Samoan Pupa problematica Mousson, 1865, the type species of Moussonia, is illustrated here for comparison (Fig. 140, Syntype ZMZ 526751, Samoa, Upolu, H = 1.9 mm). Unfortunately, there are not enough specimens of the type species available to document its inner lamellar system.