Swarming E.danica on Gordale beck - Credit Sharon Flint


The YNU recorder for mayflies (Ephemeroptera) is Mrs Sharon Flint  e-mail: flintsentomologists@btinternet.com

Ephemeroptera meaning (Greek ephemeros = lasting a day; pteron = wing)

Ephemeroptera are Hemimetabolous insects, i.e. have incomplete metamorphosis, with the larvae resembling the adult in appearance. The life cycle is divided into the four stages, egg, larvae and, uniquely, two adult stages. The subimago (Dun) which emerges from the final larval stage, moults, usually within 24 hours to become the imago (Spinner).

Reproduction and dispersal occur during the winged adult stage in the life cycle.

The following references are useful identification keys and some contain extensive ecological and distributional information.

Elliot, J.M. & Humpesch, U.M. (1983) A Key to the Adults of the British Ephemeroptera with notes on their ecology. Scientific Publications of the Freshwater Biological Association No. 47

Elliot, J.M. & Humpesch, U.M. (2010) Mayfly Larvae (Ephemeroptera) of Britain and Ireland: Keys and a Review of their Ecology. Scientific Publications of the Freshwater Biological Association. No. 66

Macadam, C & Bennet, C (2010) A Pictorial Guide to British Ephemeroptera. Field Studies Council.

The National Mayfly recording scheme can be viewed by clicking on the link below:


Sharon Flint is happy to receive specimens for identification. Identifications will be put into the NBN for the national recorders verification. Records of Mayflies can also be uploaded into:https://www.brc.ac.uk/irecord/


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Phryganea bipunctata fermale. Credit Sharon Flint
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Nemoura cinerea adult female, Malham fen. Credit Sharon Flint
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R.semicolorata adult male, Malham Tarn. Credit Sharon Flint
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