Rissoa porifera

Lovén (1846)

Description (shell):
As in Rissoa lilacina the younger parts of the last whorl bear a series of squarish pits, but costae are absent. A delicate non-costate shell, reticulate pattern of depressions prominent, visible on most whorls; varix slight. Inner lip barely spreads over the last whorl.

Up to 5 x 2.8 mm.

Horn-coloured, varix white, apex and peristome tinged brown or reddish-lilac.

Habitat as for Rissoa lilacina : occasional or locally common on weeds and amongst sandy gravel from LWST down to 50 m.

From western Ireland to Shetlands, Norway and in the Kattegat (Distr. R. porifera).