Cyllene lamarcki is a species of sea snail, a marine gastropod mollusk in the family Nassariidae, the Nassa mud snails or dog whelks.

These whorls are ornamented with longitudinal folds or ribs, narrow, and regular, finer and closer towards the lip.

Upon the body whorl, which is somewhat ventricose, the ribs are slightly arcuated throughout their whole length.

Similar striae exist at the upper part of the lowest whorl, which is flattened.

[3] The species occurs in the Atlantic Ocean off Gabon, the Gulf of Guinea and Angola