| | Insects of Britain and Ireland: the families of Trichoptera (caddis flies) |
Adults. Ocelli absent. Maxillary palps 5 segmented. The maxillary palps of males 5 segmented. The terminal segment inflexible, not multi-articulated, not annulated, and not much elongated. The scutellum without conspicuous warts.
The fore-wings 13–18 mm long; with a discoidal cell; apical forks 2–4 (males with forks 1 and 2 present and the others irregular, females with forks 1, 2, 3 and 5 present). The hind-wings similar in width to the fore-wings to wider than the fore-wings; without a discoidal cell; apical forks 1–4 (neuration not reliably interpretable in males, the females exhibiting forks 1, 2, 3 and 5).
Front tibia 2 spurred. Middle tibia 4 spurred. Hind tibia 4 spurred.
Larvae. The larvae constructing and living in transportable cases. The larval case made of sand grains and slightly curved, the hind extremity covered by a dark membrane with a central slit (before pupation, the larva closes the front of the case with a stone). The larvae eruciform. The mesonotum sclerotized; divided longitudinally into two sclerites. The metanotum sclerotized; with two horizontally elongated slerites, the anterior one broad with an excised hind margin, the posterior one narrow and widened in the middle. Abdominal segment 1 with retractable papillae; 8 with a lateral comb of fine spicules. The larva with the terminal abdominal prolegs fused basally, forming an ostensible tenth segment.
Comments. The larvae are parasitized by the ichneumonid, Agriotypus armatus Curtis.
British representation. 1 species. Genera: Odontocerum.
Illustrations. • Odontocerum albicorne: Stephens VI, 1835. • Odontocerum albicorne: wing venation and antenna. Odontocerum albicorne: fore- and hind-wings of male (1) and female (2, with the apical forks numbered), and base and middle segments of a female antenna. From Mosely (1939). • Odontocerum albicorne: thoracic terga. Odontocerum albicorne: details of the larval pronotum (above), mesonotum and metanotum, showing the sclerites. From Hickin (1952).
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 families of Trichoptera (caddis flies). Version: 27th July 2019. delta-intkey.com’.
