#semicassis

Japanese bonnet snail (Semicassis bisulcata)

A medium-sized predatory snail, not often recorded apparently, found along the Western Australian coastline and once? in South Australia.

The Cassidae (which strictly speaking should be Cassididae, and were only promoted to their own family in 2008) are nocturnal sea snails with thick shells that hunt echinoderms. The unlucky prey (usually a sea urchin) is gripped with the foot and bored into with sulphuric acid and a rasping radula.

Semicassis bisulcata

Commonly named the Japanese bonnet due to the shape of its shell, Semicassis bisulcata (Littorinimorpha - Cassidae) is a benthic sea snail found in the Indo-West Pacific.

The shell of this snail, prized by collectors, is up to 7 cm, typically 5.5 cm, with whorls rounded, entirely sculptured with spiral ribs. The outer lip of the shell is reflected, toothed on the inner edge. The background coloration white, cream, pink or blue-grey, sometimes with 4 or 5 spiral bands of brown spots; the columella and outer lip are white.

In this species eyes are located at the tentacles base as you can see in the photo.

References: [1] - [2] - [3]

Photo credit: ©James Koh [wj]