Diodora calyculata

Diodora calyculata is a species of sea snail, a marine gastropod mollusk in the family Fissurellidae, the keyhole limpets and slit limpets.

Description
The size of the shell varies between 15 mm and 26 mm.

Distribution
This species occurs in the Indian Ocean from Cape Agulhas to South Transkei, South Africa