(b) / Date unknown / Okinawa (?) / Dried specimen / UMUT

The large-sized shell reaches more than 40 cm in length, but large specimens are difficult to obtain recently. The animal is carnivorous and preferably preys on starfishes. This species is particularly well-known as a predator of crown-of-thorns starfish (Acanthaster planci) which has a frequently destructive effect on corals. Its habitat is south to Kii Peninsula, mainly from Amami Islands to the tropical Pacific, in shallow-water coral-reef environments.