Baetiscidae is a family of mayflies. It contains a single extant genus, Baetisca, native to North America with around 12 species. The family is noted for their spined armoured larvae, which live in flowing water pools and on the edges of streams where they are detritivores, consuming fine particles of organic matter. Three other extinct genera are known, extending back to the Early Cretaceous. They are closely related to Prosopistomatidae which have unusual, beetle-like nymphs as well as the extinct genus Cretomitarcys, with the three groups constituting the clade Carapacea.

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