Armored-nymphs
Guides
Baetiscidae
armored mayflies
Baetiscidae is a family of mayflies distinguished by their heavily armored nymphs bearing a robust, spiked thoracic notal shield that extends over part of the abdomen. The family contains a single extant genus, Baetisca, with approximately 12 species endemic to North America. Three extinct genera (Protobaetisca, Balticobaetisca, Koonwarrabaetisca) are known from Cretaceous and Eocene deposits, indicating a Pangean origin for the family by at least the Early Jurassic. Together with Prosopistomatidae, Baetiscidae forms the clade Carapacea, characterized by specialized larval armor.