Crisilla semistriata

(Montagu, 1808)

Shell is solid, oval conical, with five or six slightly tumid whorls. Sculpture of fine prosocline growth lines, with slight, strap-like spiral striae visible mainly below sutures on spire and toward base of the last whorl. Aperture is oval, with thickened peristome; outer lip arises tangential to the last whorl; inner lip is reflected over umbilical groove and basal area of the last whorl; umbilicus is absent.

Up to 3 x 1.6 mm.

Whitish or buff with two rows of red-brown, comma-shaped marks on the last whorl.

Body similar to Manzonia crassa , though with a short pallial tentacle on left and a longer one on right; metapodial tentacle is trilobed, opercular lobes are yellow.

Gregarious. Below stones, in fine weeds and in silted areas of rock pools below MTL; extends sublittorally to 100 m.

Distributed from Mediterranean to Norway (Distr. C. semistriata).