The family Cassidae contains medium to large size shells which occur in tropical and temperate seas. There is about 60 species, most of which occur from the intertidal down to about 100 m in depth. Most helmet shells live buried in the sand by day, coming out at night to feed on echinoderms, especially sea urchins, which they can locate by smell from at least 30 centimetre away. In the Cassidae the columellar callus extends onto the ventral surface and is referred to as the columellar shield. The margin of the columellar shield, which is the edge away from the aperture, may adhere to the ventral surface of the whorl or be free standing, and may be straight, indented, or convex. The shield itself may be smooth or sculptured.
Genus: Semicassis Mörch, 1852
Species: Semicassis glabrata Dunker, 1852
41.2 mm shell length, thin, spire, large body whorl, lip thickened, spiral line at base, white.
Cassis glabrata Dunker, 1852; Phalium glabratum Dunker, 1852
Semicassis glabrata Dunker, 1852- [Hinton (1972): 17; Hinton (1979): 18; Abbott and Dance (1982): 112; Eisenberg (1986): 80; Oliver (1989): 132; Kreipl (1997): 52-53; Thach (2005): 101; Robin (2008): 143].
Philippines; Indonesia; New Guinea: Vietnam.
This taxon has not yet been assessed for the IUCN Red List.