Tonnidae - Tun Snails

Tonnidae, the tun snails, have a broad, oval shaped shell with a large aperture. In the adult form, they lack an operculum. They inhabit soft substrate in shallow to deep tropical marine waters. When not feeding, they will usually bury themselves in the substrate leaving only the tip of their siphon exposed. They are carnivorous, feeding mainly on sea cucumbers (holothurians). They are represented by 2 species in Texas.