(Brown, 1827)
Description (shell):
Shell with elongate, slender spire; with 11 whorls and protoconch; whorls marked with strong longitudinal, closely spaced costae, and concentric grooves between costae; fairly straight-sided, sutures deep and angular; a series of concentric grooves on abapical part of last whorl. Protoconch obvious, smooth, slightly bulbous. Aperture rather squared, lip thickened; in old, thickened, individuals lip may be out-turned. Umbilicus small, usually obscured by columellar lip (T. crenata-drawing).
Size:
Up to 8 mm.
Colour:
Creamy white to yellow, banded with yellowish brown.
Distribution:
Recorded from various localities in the North Sea (Distr. T. crenata).