Heptagenioidea

Heptagenioidea is a superfamily of mayflies. Members of this superfamily are found in most parts of the world apart from the Arctic and Antarctic, with Heptageniidae being the most widely distributed family.

Heptagenioidea
Maccaffertium terminatum
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Ephemeroptera
Suborder:	Pisciforma
Superfamily:	Heptagenioidea
Families
Arthropleidae Heptageniidae Isonychiidae Oligoneuriidae Pseudironidae

Heptagenioidea probably originated in the Jurassic period when mayflies started breeding in flowing water, the mouthparts and forelegs becoming adapted to passive feeding. The ancestors of the new group had bred in still water, and the opportunities provided by the change in environment encouraged rapid radiation.^[1]