Demoulia abbreviata, common name : the obtuse demoulia, is a species of sea snail, a marine gastropod mollusk in the family Nassariidae, the Nassa mud snails or dog whelks.

The suture is deep and canaliculated, the exterior edge of which is slightly rounded and surrounded by a white band, alternated with fawn-colored blotches.

The white aperture is subrotund, narrowed at the upper part and dilated inferiorly.

The thin outer lip is crenulated upon the edge, and marked interiorly with very prominent transverse striae .

It forms, from the middle to the base, a thick and projecting callus, which is terminated by a very apparent fold, and by two guttules.