Fissurella afra is a species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of sea snail

Sea snail

Sea snail is a common name for those snails that normally live in saltwater, marine gastropod molluscs....

, a marine gastropod mollusk in the family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Fissurellidae, the keyhole limpets.

Description

Fissurella afra has on ovate-oblong and convex shell. The bull-fish within it is painted with brownish-violet rays and is white within. For the rest it is ovate, conicale, and obtuse at its summit; its fissure is ovate and contracted in the middle. Fissurella afra is also very finely striated radiately, and marked in the same way with radiating bands of a violaceous-brown on a yellowish-white ground.
This species is often confused with the D. nimbosa, but its summit is more elevated and the aperture is carried more forward.

Length 9, breath 7, alt. 5 ½ lines.

Distribution

This particular species of mollusc is native to the Islands of the Archipelago or Capo Verde, in particular that of St. Iago .