British Insects: the Families of Diptera


L. Watson and M. J. Dallwitz


Gout-fly, Frit-fly.

Adult insects. Very small to small; robustly-built; winged. Antennae 3 segmented; ‘modified’; aristate; the arista dorsal (pubescent or bare). The second antennal segment not grooved. Ptilinal suture clearly defined. Ocelli present; 3. Post-vertical orbital bristles present, or absent (head bristles weakly developed or absent); convergent. Mouthparts functional. The maxillary palps 1 segmented; porrect. Vibrissae absent. 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; without a sub-apical cell; without a closed anal cell. The costa with one break (near the end of the sub-costa). Sub-costa apparent, or absent or only dubiously identifiable; terminating blind, or joining vein 1 well short of the costa (well short). Wing vein 6 present (weak), or absent; if detectable, falling short of the wing margin. Wings with the lower calypter much reduced or absent. Tibiae without a dorsal pre-apical bristle. Hind tibiae without strong bristles in the basal 4/5.

Larvae and pupae. The larvae terrestrial; phytophagous (many in the young shoots and stems of grasses and other plants), or predatory (some, on aphids); acephalic. The pupae enclosed within a puparium.

Comments. Small or very small, bristle-less flies with reduced wing venation and a characteristic large ocellar triangle. Often black, yellow and black or green and black.

Classification. Suborder Brachycera; Division Muscomorpha Schizophora Acalyptratae; Superfamily Carnoidea.

British representation. 175 species in Britain. Genera 39; Aphanotrigonum, Calamoncosis, Camarota, Cetema, Chlorops, Conioscinella, Cryptonevra, Dicraeus, Diplotoxa, Elachiptera, Epichlorops, Eribolus, Eurina, Eutropha, Gampsocera, Gaurax, Hapleginella, Incertella, Lasiambia, Lasiosina, Lipara, Melanochaeta, Melanum, Meromyza, Microcercis, Neohaplegis, Oscinella, Oscinimorpha, Oscinisoma, Platycephala, Polyodaspis, Pseudopachychaeta, Rhopalopterum, Siphonella, Siphunculina, Speccafrons, Thaumatomyia, Trachysiphonella, Tricimba.

Illustrations. • Platycephala planifrons: B. Ent. 725. • Platycephala planifrons: B. Ent. 725, legend+text. • Platycephala planifrons: B. Ent. 725, text cont.. • Camarota curvipennis and Platicephala planifrons (from Walker). • Oscinella frit.

To view the illustrations with detailed captions, go to the interactive key. This also offers 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.

Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2003 onwards. British insects: the families of Diptera. Version: 1st January 2012.’.