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| Insects of Britain and Ireland: the families of Diptera |
Omphralidae
Window-flies.
Adult insects. Small. Antennae 3 segmented (pendulous, the two basal segments short and the third elongated); ‘modified’; with a non-annulated terminal segment; not aristate. Ptilinal suture absent or weakly defined. Eyes asymmetric, nearly or quite connected above the antennae, or rounded, well separated. Mouthparts functional (proboscis very short); non-piercing. The maxillary palps 1 segmented, or 2 segmented; porrect. Wings with a discal cell (large); with a subapical cell; with a closed anal cell. The anal cell relatively long. Wings with 6 cells between vein 3 and the anal cell. Sub-costa apparent; reaching the costa independently of vein 1. Wing vein 3 distally forked. Wing vein 6 present; reaching the wing margin, or falling short of the wing margin. Wing vein 7 present; falling short of the wing margin. Wings with the lower calypter much reduced or absent. Feet without a triple pad.
Larvae and pupae. The larvae terrestrial; saprophagous (in rotting vegetation and birds' nests), or predatory (on other insect larvae); hemicephalic. The pupae without a puparium.
Comments. Small, sturdy, narrowly-oblong, black flies without bristles. Resting with wings parallel over the abdomen.
Classification. Suborder Brachycera; Division Asilomorpha; Superfamily Asiloidea.
British representation. 2 species in Britain, or 3 species in Britain. Genera 1; Scenopinus.
Illustrations. • Scenopinus fenestralis (from Walker). Scenopinus fenestralis, with details of head from beneath (16a), proboscis (16b), antenna (16c), and extremity of tarsus (16d). From Walker (1851, Plate II), with 2mm scale 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’.
