Revised systematics, phylogeny, and paleontology of the mayfly family Baetiscidae (Insecta: Ephemeroptera)

The systematics of all known extant and fossil taxa of the mayfly family Baetiscidae is reviewed. Previously described fossil Baetiscidae are critically reviewed and their systematic position is re-evaluated. Added herein is the description of Balticobaetisca bispinata sp. nov., a new fossil mayfly from Eocene Baltic Amber. Also described for the first time is the putative adult of Protobaetisca bechlyi Staniczek, 2007 from the Cretaceous Crato Formation of Brazil. Based on external morphological characters of nymphs and adults, we present the first integrated cladistic analysis of both fossil and extant Baetiscidae, which revealed the monophyly of the respective fossil and extant genera and their phylogenetic splitting sequence as Cretomitarcys + (Protobaetisca + (Balticobaetisca + Baetisca))