Ephemeroptera

order of insects Ephemeroptera (Ephemeroptera) is an order comprising closely related families of organisms. It contains 6 families with 8 known species. This includes the family groups Ameletidae, Baetidae, Caenidae, Ephemerellidae, Ephemeridae, and Heptageniidae. Among its members, 1 species are currently classified as threatened (Critically Endangered, Endangered, or Vulnerable). It belongs to Insects (Insecta).