Order: Ephemeroptera (mayflies)

Life > Eukaryotes > Opisthokonta > Metazoa (animals) > Bilateria > Ecdysozoa > Panarthropoda > Tritocerebra > Phylum: Arthopoda > Mandibulata > Atelocerata > Panhexapoda > Hexapoda > Insecta (insects) > Dicondyla > Pterygota

Adult mayfly resting on rock. [photo HG Robertson, Iziko ©]

Mayfly nymph on bottom of stream. Note the gills on the abdomen for breathing underwater. [photo HG Robertson, Iziko ©]

Adult mayflies are very short-lived, typically only living about a day. They do not feed in the adult stage so as soon as the adult female emerges, she needs to mate and lay her eggs as soon as possible. Mating takes place in swarms, typically over water but also sometimes over a prominent landmark near the water. Males fly up and down in the swarm and mating takes place in flight. Eggs are laid in the water, usually by depositing them in flight although there are species that crawl into the water and lay their eggs on the bottom of the water body. Nymphs are aquatic and in most species feed on detritus and algae on the bottom of the stream although there are carnivorous and filter-feeding species as well. Mayflies are unique among insects in having a winged subimago stage which then moults into the winged imago (adult) stage. In other insects there is no more moulting after they have moulted into a stage with functional wings.

A total of 402 species of mayfly have been recorded from South Africa (South African Animal Checklist (SANBI); October 2018).

Further Reading

• McCafferty, W.P. 1981. Aquatic Entomology. The Fishermen's and Ecologists' Illustrated Guide to Insects and Their Relatives. Jones and Bartlett Publishers, Inc. Boston 448 pp. (Chapter 7 . Mayflies. pp. 91-124).

• Skaife, S.H. 1979. African Insect Life. Struik, Cape Town, pp. 33-35.

Text by Hamish Robertson