General description (after 312 shells from 24 localities). — A small but solid shell, conical with a blunt top. The protoconch is of type B, tending to C (intorted). There are three or four flat teleoconch whorls, the last one rather high. The suture is broad and deep, about vertical or somewhat oblique. The ribs are straight or very slightly curved, about vertical or somewhat leaning to the right or to the left. They are sharply outlined and about as broad as the interstices. On the initial whorls there is always one spiral ridge on the base of the whorls, bordering the ribs on their abapical side. Below that, the whorl constricts considerably. Sometimes a second, narrower, spiral can be seen within the suture. The last whorl has, just above the aperture, one spiral ridge, on which the ribs finish and below which the whorl also strongly constricts. Next to the aperture there are still four (sometimes five) spiral ridges. The interspaces are as broad as, or slightly narrower than, the spirals. Well-preserved and fresh shells show, in these interstices, very fine riblets as a continuation of the real ribs, but in a strongly prosocline direction (the same riblets can be seen within the sutures between the whorls). The aperture is egg-shaped; the tooth well visible. The umbilical chink
is insignificant to absent. Length 1,5-2.1 mm, LW 56-66%, A 31-39%, L/B 1.9-2.5, B/b 1.4-2.0 (based on 25 shells).

In the two samples from San Carlos (Taragona, Spain) a few shells of a different type were present: the last whorl is more convex, the ribs are much more opisthocline and are slightly flexuous. On the last and penultimate whorls there is, just above the normally single spiral ridge, one more and much narrower spiral, which is placed between the ribs. Furthermore there are six, instead of four or five, spirals next to the aperture. The protoconch is more tending towards type B. See under C. spiralis for the differences with this species. The difference with C, emaciate is clear: C. emaciata is much more slender, the shell is thinner, more fragile, the whorls convex, and at the base fine, close-set striae can be observed, instead of the pro¬nounced spiral ridges in C. brusinai.

The entire Mediterranean area up to Mauritania.