The aperture is either oblong or transversely oval, and longer than wide or the reverse.

Stomatia is closely allied to Stomatella, differing in the generally more elongated shell with a series of short folds or puckers below the sutures.

The foot is large, fleshy, tubercular, greatly produced posteriorly.

The epipodium is fringed, with a more prominent fimbriated lobe behind the left tentacle, and on the right there is a slightly projecting fold or gutter leading to the respiratory cavity.

[3] This marine genus occurs in tropical Indo-West Pacific, Oceania, Korea and Australia.