British Insects: the Families of Diptera


L. Watson and M. J. Dallwitz


Blow-flies, Green-flies, Bluebottles, Flesh-flies.

Life style parasitic (sometimes, in the larval stage), or non-parasitic; on when parasitic, slugs and snails and Annelid worms.

Adult insects. Small to large; robustly-built. Antennae 3 segmented; ‘modified’; aristate; the arista dorsal (and long-plumose). The second antennal segment distinctly grooved above. Ptilinal suture clearly defined. Eyes asymmetric, nearly or quite connected above the antennae (some males), or rounded, well separated. Mouthparts functional, or non-functional (Hypodermatinae); non-piercing. The maxillary palps 1 segmented (or lacking, Hypodermatinae); porrect. Vibrissae present, or absent (?). Thorax with the dorsal suture continuous across the middle; with well defined posterior calli. Postscutellum absent or weakly developed. Hypopleural bristles present (in a ‘fan’). The post-humeral bristle located lower on the thorax than the pre-sutural bristle. Wings with a discal cell; with a subapical cell; with a closed anal cell. The anal cell short. The costa unbroken. 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; 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 (feeding mainly on nectar, honey-dew, etc., and on the liquid products of decomposition).

Larvae and pupae. The larvae terrestrial; saprophagous, or coprophagous, or consuming stored produce, or mycophagous, or parasitic (e.g., on worms and snails); acephalic. The pupae enclosed within a puparium.

Comments. Often metallic green or blue flies.

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

British representation. 38 species in Britain. Genera 14; Angioneura, Bellardia, Calliphora, Cynomya, Eggisops, Eurychaeta, Lucilia, Melanomya, Melinda, Phormia, Pollenia, Protocalliphora, Protophormia, Stomorhina.

Illustrations. • Calliphora vomitoria and Cynomyia mortuorum (from Walker).

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.’.