Family Neoephemeridae Traver 1935 (mayfly)
Insecta - Ephemeroptera - Neoephemeridae
Parent taxon: Caenoidea according to T. H. Ogden et al. 2009
See also Jacobus and McCafferty 2006, Kluge 2004, McCafferty and Edmunds 1979 and Sinitshenkova 1999
Sister taxon: Caenidae
Subtaxa: Neoephemera Potamanthellus
Ecology:
Distribution:
• Oligocene of United States (1: Montana collection)
• Eocene of United States (1: Washington)
Total: 2 collections each including a single occurrence