Demoulia

Demoulia is a genus of marine gastropod mollusks, commonly known as dog whelks or Nassa mud snails, and belongs to the family Nassariidae. The shell of these sea snails is ovate and globose, with a soft, downy outer layer called an epidermis. Its spire is short and conical, ending in a papilla-like tip, and the whorls are flattened.

The opening of the shell is oval, with a thickened inner lip that has a ridge at the back, while the outer lip is narrowed, thickened on the outside, and lined with folds on the inside. Species in this genus include Demoulia abbreviata, Demoulia nataliae, Demoulia obtusata, Demoulia tryoni, Demoulia ventricosa, and several extinct forms such as Demoulia conglobata, Demoulia pupa, and Demoulia zbyszewskii. Some names once considered separate species, like Demoulia kurodai, Demoulia pulchra, and Demoulia retusa, are now recognized as synonyms of other species.