(a) / Date unknown / Locality unknown / Dried specimen / UMUT

This shell is considerably swollen and attains more than 30 cm in height. The animal is large, covering most of the shell and lacking an operculum. This species is carnivorous and deposits eggs in egg capsules after internal fertilization. Its habitat consists in shallow sandy bottoms in the tropical Western Pacific. The scientific name indicates a melon-shaped shell with an apical depression.