Erosaria spurca: Usually the colouring pattern is dirty white with fine variagations yellow-brown in colour on the back, but it is fairly variable, and this is the reason for several variety names as (albida, flavida, limpida, pantherina, viridula, flaveola and so on). The margin, defined by a series of little grooves, and the inferior zone are of an uniform yellowish colour pattern. Even the mantle, that usually is red-brown in colour and that camouflages this species, can assume several shades.
The protoconch sculpture, made by a thick and regular reticulum, is a characteristic one, no clear in the adults (see confrontation with Luria lurida protoconch). It is a carnivourus species, typical of the hard bottoms and, as per the other Cypraeidae, it is in the special habit to cover the shell with the mantle, so it is possible to find imaged shells dead but still bright and perfectly preserved. The male and female species are separated and there is often a remarkable difference in the sizes among one another. The female shell lays several tens of thousands eggs into egg capsules; the hatching occurs after 2-3 weeks. By day it is almost always hidden under dead corals, stones, fragments of different nature, while by night it goes out to get some food. It is a protected species.

Erosaria spurca: Shell obovate, more or less inflated; lips not greatly produced above; aperture slightly curved, a very little wider below; teeth rather strong, short; sides pitted; back whitish or buff, clouded and mottled with fulvous yellow, the pits and sides often spotted with brown.
Length, 30; diameter, 18 mm.

Erosaria spurca: Distribution: common all over the Mediterranean, but mainly in the Centre-Southern area, never common in the Adriatic. Habitat: this species lives under stones or into cracks from a few metres depth up to 30-40 m depth.