| | Insects of Britain and Ireland: the genera of Ephemeroptera |
Imago. The compound eyes distinctly two-lobed (in males), or rounded (in females); upper lobe in the males, turbanate.
Fore-wings with R5 detached basally from R4. The marginal fore-wing veinlets single. Hind-wings present. The hind-wings of the female imagines no more than one fifth the length of the fore-wings. The hind-wing costa with a conspicuous projection. Hind tarsi with 4 moveable segments, or with 2–3 moveable segments (?).
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. 2 species; C. luteolum (Small Spurwing or Pale Watery Dun, Small Spurwing male Spinner, and Little Amber female Spinner), and C. pennulatum (Large Spurwing Dun and male Spinner, Large Amber female Spinner).
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, 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. See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2003 onwards. Insects of Britain and Ireland: the genera of Ephemeroptera. Version: 11th April 2022. delta-intkey.com’.