(Forbes, 1846)
Description (shell):
Shell a moderately tall, rather narrow cone, similar to that of Turbonilla jeffreysii in general appearance but is narrower and thinner, and its seven whorls differ in details of shape. Whorls are distinctly tumid, spire not turreted in profile. Sutures far below periphery of each whorl. Last whorl occupies just less than half the shell height. Ornament of narrow costae with spiral ridges in the interstices. The costae are commonly flexuous, narrower and more close-set than in T. jeffreysii , and number 20-22 on the last whorl, 19-20 on the penult. The oval aperture occupies about 30 % of shell height. Shell without marked umbilical groove, umbilicus or visible tooth.
Size:
Up to 6 x 2 mm.
Colour:
Tawny with three orange-brown spiral bands on last whorl. The spiral bands of colour are of regular occurrence.
Animal:
The tentacles are long, narrow, triangular and grooved laterally. The mentum is long and narrow, grooved dorsally and bifid distally. The eyes are close together. The foot is short, broad anteriorly and slightly concave with anterolateral points, narrow and pointed posteriorly. Flesh a pale reddish brown.
Habitat:
The animals occur 5-10 m deep, usually with the hydroids Halecium and Antennularia , on which they feed.
Distribution:
The geographical range of this species is inaccurately known since it has not always been distinguished from Turbonilla jeffreysii ; not in the southern North Sea (Distr. T. rufescens).