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Discussion, insects and people from the 2018 BugGuide Gathering in Virginia, July 27-29

Photos of insects and people from the 2015 gathering in Wisconsin, July 10-12

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Species Cloeon dipterum

Cloeon dipterum - male Cloeon dipterum - male Mayfly in September - Cloeon dipterum - female orange Mayfly? - Cloeon dipterum Mayfly - Baetidae? - Cloeon dipterum Baetid imago - Cloeon dipterum - male Baetid subimago - Cloeon dipterum - female Mayfly - Cloeon dipterum - male
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Ephemeroptera (Mayflies)
Suborder Pisciforma
Family Baetidae (Small Minnow Mayflies)
Genus Cloeon
Species dipterum (Cloeon dipterum)
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)
May-Sep (BG data)
Life Cycle
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.