''Heptagenioidea'' is a superfamily of

mayflies Mayflies (also known as shadflies or fishflies in Canada and the upper Midwestern United States, as Canadian soldiers in the American Great Lakes region, and as up-winged flies in the United Kingdom) are aquatic insects belonging to the order ...

. 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 probably originated in the

Jurassic The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of ...

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.

References

{{Taxonbar, from=Q3133322 Mayflies Insect superfamilies