Prosopistomatidae is a family of mayflies. There is one extant genus, Prosopistoma, with several dozen species found across Afro-Eurasia and Oceania. They are noted for their unusual beetle-shaped larvae, which live beneath rocks and stones along the gravelly lower reaches of rivers. Their ecology is unclear, but they are probably carnivorous. They are closely related to Baetiscidae, with both families being placed in the Carapacea.

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