Synonyms and other taxonomic changes
Cloeon dipterum (Linnaeus)
Orig. Comb: Ephemera diptera Linnaeus, 1761
Syn: Cloeon cognatum Stephens 1835
Holarctic, widespread Eurasia; Canada & ne. US(1) Map(2)
Ovoviviparous, meaning a mated female holds her eggs internally until embryonic development is complete (about 18 days), after which she lays them in water and they hatch almost immediately: Video
- Video credit: David H. Funk, Stroud Water Research Center
First recorded in the US in 1953, in Illinois; now widespread. Probably introduced.