Caenoidea

Caenoidea
Caenis horaria
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Ephemeroptera
Suborder:	Pannota
Superfamily:	Caenoidea

Caenoidea is a superfamily of mayflies in the suborder Pannota. Members of this superfamily can be distinguished from those of Ephemerelloidea by the fact that the gills of the nymphs are filamentous.

The following families are recognised:

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Wikipedia