Nassarius distortus

Nassarius distortus, commonly called the distorted nassa, is a marine gastropod mollusc belonging to the family Nassariidae, which includes the Nassa mud snails and dog whelks. Its shell, which ranges from 18 mm to 35 mm in size, is ovate, conical, smooth, polished, and whitish. Beneath the suture runs a rose-colored band, and three more such bands encircle the middle of the lowest whorl; the central band is broader and more noticeable. The spire consists of seven slightly convex whorls, each adorned with numerous, slightly raised longitudinal ribs that resemble folds.

The upper edge of each whorl is somewhat flattened. At the base of the lowest whorl, two distinct ridges are present. The suture is bordered by rounded tubercles positioned between the folds, forming a necklace-like pattern.

The white aperture is ovate and narrowed above by a transverse fold of the callosity. The outer lip is slightly truncated, finely toothed along the lower edge, and marked internally with transverse striae. The columellar edge is covered by a fairly thick callosity that spreads a little onto the shell’s belly. This species has a wide distribution across the Indo-West Pacific, including off the coast of Queensland, Australia.