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| Insects of Britain and Ireland: the families of Diptera |
Aulacogastridae
Adult insects. Very small (about 2.5 mm long); winged. Antennae 3 segmented (third segment short, rounded); ‘modified’; aristate; the arista dorsal (pubescent). The second antennal segment not grooved. Ptilinal suture clearly defined. Ocellar bristles absent. Post-vertical orbital bristles absent. Mouthparts functional. The maxillary palps 1 segmented; porrect. Vibrissae present (two strong pairs). Thorax without a continuous dorsal suture; without well defined posterior calli. Wing venation incomplete, in the sense of lacking one or more of the cells. Wings without a discal cell; with a closed anal cell. The anal cell short. The costa with one break (at the apex of the sub-costa). Sub-costa apparent; reaching the costa independently of vein 1. Wing vein 4 extending far beyond the end of the first basal cell (the first basal cell about 1/5 the length of the wing). Wings with the lower calypter much reduced or absent. Tibiae with a dorsal pre-apical bristle to without a dorsal pre-apical bristle (the bristle indistinct). Hind tibiae without strong bristles in the basal 4/5.
Larvae and pupae. The larvae terrestrial; saprophagous (on decomposing material around tree wounds); acephalic. The pupae enclosed within a puparium.
Comments. A shining brown fly, with a large mouth.
Classification. Suborder Brachycera; Division Muscomorpha Schizophora Acalyptratae; Superfamily Opomyzoidea.
British representation. 1 species in Britain. Genera 1; Aulacigaster leucopeza.
Illustrations. • Aulacigaster. 1, Aulacigastridae: head of Aulacigaster leucopeza. 2a and 2b, Canacidae: wing and head of Canace nasica. 3, Diastatidae: head of a Diastata species. 4, Carnidae: Carnus sp., wing. 5a and 5b, Milichiidae: leg of Leptometopa latipes (5a), and head of Phyllomyza securicornis (5b). 6, Odiniidae: Odinia sp., wing. 7a and 7b, Tethinidae: Tethina sp., head and wing. 8, Periscelididae: Periscelis winnertzi, wing. From Colyer and Hammond (1951).
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’.
