Aplysia concava
Aplysia concava, common name the Norfolk Island aplysia, is a species of gastropod mollusc in the genus Aplysia, family Aplysiidae.
Description
The length of the species attains 75 mm.The shell is horny, brown, and thinly constructed. It presents an arched, ventricose, and obliquely subovate form with a smooth surface. The apex is elevated and rounded, featuring a posterior auriculation. Its upper margin is sloped and excavated. The outer lip is rather convex, and the lower margin is rounded. The dorsal margin is arched, rounded, and thinly reflected near the apex, inclining obliquely towards the lower end.