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| Insects of Britain and Ireland: the families of Diptera |
Rhyphidae, Phryneidae, Sylvicolidae
Gnat-like flies.
Adult insects. Small to medium-sized; slender-bodied to robustly-built; stilt-legged, or not stilt-legged. Antennae 8–16 segmented; ‘simple’; 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. Thorax without a continuous dorsal suture. Wing veins reaching the margin 9, or 10. Wing vein 7 falling short of the margin. Wings with a discal cell; without a sub-apical cell; without a closed anal cell. The costa not extending around the entire wing. Sub-costa apparent; reaching the costa independently of vein 1. Wing vein 6 present; reaching the wing margin. Wing vein 7 present; falling short of the wing margin. Wings with the lower calypter much reduced or absent; patterned (mottled). Tibiae spurred (apically).
Larvae and pupae. The larvae more or less aquatic, or terrestrial; saprophagous, or coprophagous, or consuming stored produce (sometimes in honeycombs, cider and wine); eucephalic. The pupae without a puparium.
Comments. Flies sometimes dancing in swarms.
Classification. Suborder Nematocera; Division Psychodomorpha; Superfamily Anisopodoidea.
British representation. 4 species in Britain. Genera 1; Sylvicola.
Illustrations. • Sylvicola fenestralis (Domestic Gnat-like fly: B. Ent. 102). • Sylvicola fenestralis (detail: B. Ent. 102). • Sylvicola fenestralis (dissections: B. Ent. 102). • Sylvicola fenestralis (B. Ent. 102, legend+text). • Sylvicola fenestralis (B. Ent. 102, text cont.). • Sylvicola cinctus (from Walker). Sylvicola cinctus female. 8a, Sylvicola cinctus, head of male; 8b, antenna; 8c, mouth with long horny labrum and tongue. From Walker (1856, Plate XXVIII), with approximate insect length 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’.
