Crepidula atrasolea is a species of small sea snail, a slipper snail, a marine gastropod mollusk in the family Calyptraeidae, the slipper snails or slipper limpets, cup-and-saucer snails, and hat snails.

This species is similar to Crepidula plana and Crepidula depressa, but it can be distinguished from them on the basis of the dark pigment on the foot, and direct-developing embryos. DNA sequence data shows that these three species are closely related within the genus Crepidula, but are not closely related to other flat white species of Crepidula, which occur throughout the phylogeny of the genus.

A video showing the differences between the species is available CollinLab videos

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