This opisthobranch has a limpet-like shell which is composed primarily of protein, not calcium carbonate.
This species of false limpet occurs in the northeastern Atlantic including the British Isles and the Mediterranean Sea.
T. perversa feeds on the sponge species Aplysina aerophoba.
Underwater photos at Akrotiri 19/11/2016 by Kostas Aristeidou
Photos by Costas Constantinou