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| Insects of Britain and Ireland: the families of Diptera |
Excluding Scatopsidae
March-flies.
Adult insects. Small; slender-bodied to robustly-built; hairy bodied; not stilt-legged. Antennae short, 8–16 segmented (the segments stout and closely set); short and stout; ‘simple’ (usually shorter than the thorax); not aristate. Ocelli present; 3. Eyes asymmetric, nearly or quite connected above the antennae (often, in males), or rounded, well separated. The maxillary palps 3–5 segmented; drooping. Vibrissae absent. Wing veins reaching the margin 5–8 (? -fewer than 9). Wings without a discal cell; without a sub-apical cell; without a closed anal cell. The costa extending around the entire wing, or not extending around the entire wing. Sub-costa apparent; terminating blind. The leading edge veins markedly stronger than the rest. Wing vein 7 present; falling short of the wing margin. Wings with the lower calypter much reduced or absent. Tibiae spurred (front tibiae with apical large, strong spurs or circlets of spines). Feet with a triple pad beneath the tarsal claws, or without a triple pad (?). Neither parasitic nor predatory (pollinators).
Larvae and pupae. The larvae terrestrial; phytophagous, or saprophagous (in decaying vegetation, in soil); eucephalic. The pupae without a puparium.
Comments. Usually dark, hairy flies, “of rather grotesque appearance”.
Classification. Suborder Nematocera; Division Bibionomorpha; Superfamily Bibionoidea.
British representation. 20 species in Britain. Genera 2; Bibio, Dilophus.
Illustrations. • Bibio venosus (Veined Crane-fly: B. Ent. 138). • Bibio venosus (detail: B. Ent. 138). • Bibio venosus (dissections: B. Ent. 138). • Bibio venosus (B. Ent. 138, legend+text). • Bibio venosus (B. Ent. 138, text cont.). • Dilophus febrilis (from Walker). Dilophus febrilis: 4, female; 4a, head of male; 4b, palp of male; 4c, antenna of male; 4d, anterior tibia and tarsus; 4e, apex of anterior tarsus, with claws and pulvilli. From Walker (1856, Plate XXIV), with 2mm scale added. • Bibio marci (from Walker). 3a-3c, Bibio marci, female: details of head (3a), antenna (3b), wing (3c), and fore-leg (3d). 5, Bibio marci, male. From Walker (1856, Plates XXIV and XXIX), with approximate length of the male insect (front of head to tip of abdomen) added.
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 Diptera. Version: 14th April 2022. delta-intkey.com’.
