Acmaeidae is a family of sea snails, specifically true limpets, marine gastropod mollusks in the superfamily Lottioidea and the subclass Patellogastropoda (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).

[1] Listed as valid family in Bouchet & Rocroi (2005) but this classification revised following the molecular phylogeny of Nakano & Ozawa (2007).

Acmaeinae, including Erginus, was found to be paraphyletic.

However, this synonymy was subsequently found incorrect, having been the result of contaminated samples, and Acmaea mitra and a related species, Niveotectura pallida form a well-supported clade outside of the Lottiidae, and Acmaeidae was re-established.

[2]