British Insects: the Genera of Ephemeroptera
Imago. The compound eyes rounded.
Fore-wings with R5 detached basally from R4. Hind-wings absent. The hind-wings of the female imagines more than one fifth the length of the fore-wings. Hind tarsi with 4 moveable segments. The first segment of the hind tarsus about three times as long as the second.
The abdomen with two tails.
Nymph. The outer tails hairy on the inner side only. Gills mostly at the sides of the abdomen; not fringed with filaments on both sides.
Classification. Superfamily Baetoidea. Family Baetidae.
British representation. 1 species; P. bifidum (Pale Evening or Pale Watery Dun, Pale Evening Spinners).
To view illustrations with legends giving names in current use, go to the interactive key. This also offers full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, and distributions of character states within any set of taxa, as well as source references and other relevant material.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2003 onwards. British insects: the genera of Ephemeroptera. Version: 29th December 2011. http://delta-intkey.com’.