British Insects: the Families of Diptera


L. Watson and M. J. Dallwitz



Life style parasitic (in the larval stage); on Arthropods in general.

Adult insects. Small to large; robustly-built (mainly), or slender-bodied (Dexiinae). Antennae 3 segmented; ‘modified’; aristate; the arista dorsal (bare, pubescent or plumose). The second antennal segment distinctly grooved above. Ptilinal suture clearly defined. Ocelli present; 3. Eyes rounded, well separated (usually well separated). Mouthparts functional. The maxillary palps 1 segmented; porrect. Vibrissae present, or absent (?). Thorax with the dorsal suture continuous across the middle; with well defined posterior calli. Postscutellum present and well developed. Hypopleural bristles present (as a ‘fan’). Wings with a discal cell; with a subapical cell; with a closed anal cell. The anal cell short. Sub-costa apparent; reaching the costa independently of vein 1. The leading edge veins not noticeably stronger than the rest. Wings exhibiting a sharp bend in vein 4 (usually bent abruptly towards vein 3 at the apex); without a ‘vena spuria’. Wing vein 6 present; falling short of the wing margin. Wings with a well developed lower calypter. Hind tibiae with strong bristles in the basal 4/5. Neither parasitic nor predatory (? - mostly found among vegetation, especially on flowers).

Larvae and pupae. The larvae parasitic; endoparasitic (in a wide range of arthropods); acephalic. The pupae enclosed within a puparium.

Classification. Suborder Brachycera; Division Muscomorpha Schizophora Calyptratae; Superfamily Oestroidea.

British representation. 247 species in Britain. Genera 137; with only Carcelia, Exorista, Macquartia and Siphona represented by more than about five species.

Illustrations. • Allophora, Cylindromyia, Gonia, Gymnosoma, Phania, Siphona, Tachina, Zomophyia (from Walker). • Blondelia, Prosena, Trixa (from Walker). • Gonia picea (Red-headed Gonia: B. Ent. 533). • Gonia picea (detail: B. Ent. 533). • Gonia picea (dissections: B. Ent. 533). • Gonia picea: B. Ent. 533, legend+text. • Gonia picea: B. Ent. 533, legend+text. • Cylindromyia brassicaria: B. Ent. 629. • Cylindromyia brassicaria: B. Ent. 629, legend+text. • Cylindromyia brassicaria: B. Ent. 629, text cont.. • Prosena siberita: B. Ent. 665. • Prosena siberita: B. Ent. 665, legend+text. • Phasia obesa: B. Ent. 697. • Phasia obesa: B. Ent. 697, legend+text. • Phasia obesa: B. Ent. 697, text cont.. • Gonia divisa (as G. auriceps): Stephens 1846.

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.’.