Afrolittorina knysnaensis

Afrolittorina knysnaensis, common name the southern periwinkle, is a species of sea snail, a marine gastropod mollusk in the family Littorinidae, the winkles or periwinkles.

Description
The size of the shell varies between 9 mm and 15 mm. Its color varies from brown with a pattern of dots with a dark ring around its every whorl, to pure black. The smooth shell has a conical shape with a short spire. The aperture is subcircular and has a transparent, horny operculum.

Distribution
This marine species occurs off Namibia to Southern KwaZuluNatal; in the Indian Ocean off Réunion.