Fossil-taxon
Guides
Neoephemera
large squaregill mayflies
Neoephemera is a genus of large squaregill mayflies in the family Neoephemeridae, established by McDunnough in 1925. The genus contains approximately six extant species distributed across North America and Asia, plus one extinct species from the Eocene of Washington State. Species range from moderate to large size within the family, with body lengths varying considerably. The genus has been subject to taxonomic revision, with at least one species (N. projecta) transferred to a new genus Pulchephemera based on phylogenetic analysis of plesiomorphic characters.