British Insects: the Families of Diptera


L. Watson and M. J. Dallwitz


Excluding Ocydromiinae and Tachydromiinae.


Adult insects. Very small to medium-sized; slender-bodied to robustly-built; stilt-legged, or not stilt-legged. Antennae 3 segmented (third segment not annulated); ‘modified’; with a non-annulated terminal segment; aristate, or not aristate; the arista when present, apical (but sometimes downwardly directed). Ptilinal suture absent or weakly defined. Ocelli present; 3. Eyes rounded, well separated (and usually nicked in the inner margin, near the bases of the antennae). Mouthparts functional (proboscis usually rigid, sometimes very long); adapted for piercing. The maxillary palps 1 segmented, or 2 segmented; porrect. Wings usually with a discal cell; without a sub-apical cell; with a closed anal cell, or without a closed anal cell. The anal cell when present, relatively long (but falling well short of the margin), or short. The costa not extending around the entire wing. Sub-costa apparent; reaching the costa independently of vein 1 (e.g., Clinocera, Phyllodromia), or terminating blind (e.g., Rhamphomyia). The leading edge veins not noticeably stronger than the rest. Wing vein 3 distally forked. Wing vein 6 present, or absent; 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; patterned, or unpatterned. Feet with a triple pad beneath the tarsal claws (occasionally), or without a triple pad. The hind tarsi normal. Predatory (on other, smaller arthropods, mainly Diptera).

Larvae and pupae. The larvae aquatic, or terrestrial; saprophagous, or predatory; hemicephalic. The pupae without a puparium.

Comments. Small to medium sized, mostly bristly flies, folding the wings over the abdomen at rest. Not metallic. Sometimes dancing in swarms, cf. chironomids.

Classification. Suborder Brachycera; Division Asilomorpha; Superfamily Empidoidea.

British representation. 208 species in Britain. Genera 17; Chelifera, Chelipoda, Clinocera, Dolichocephala, Dryodromya, Empis, Gloma, Heleodromia, Heterodromyia, Hilara, Hormopeza, Iteaphila, Kowarzia, Phyllodromia, Ragas, Rhamphomyia, Trichoopeza, Wiedemannia.

Illustrations. • Clinocera, Dolichocephala, Empis, Heleodromia, Hilaria, Ragas, Wiedemannia (from Walker). • Chelifera, Heleodromia, Hemerodromia, Phyllodromia, Rhamphomyia (from Walker). • Wiedemannia bistigma Curtis (Tachydromiinae: Stigma-spotted Heleodromia: B. Ent. 513). • Wiedemannia bistigma (detail: B. Ent. 513). • Wiedemannia bistigma (dissections: B. Ent. 513). • Wiedemannia bistigma (B. Ent. 513, legend+text). • Wiedemannia bistigma (B. Ent. 513, text cont.). • Empis borealis (Northern Empis: B. Ent. 018). • Empis borealis (detail: B. Ent. 018). • Empis borealis (dissections: B. Ent. 018). • Empis borealis: B. Ent. 018, legend+text. • Empis borealis: B. Ent. 018, text cont.. • Hilara curtisi (Fan-footed Empida: B. Ent. 130). • Hilara curtisi (B. Ent. 130, legend+text). • Hilara curtisi (B. Ent. 130, text cont.). • Rhamphomyia barbata (Feather-legged Dancing Fly: B. Ent. 517). • Rhamphomyia barbata: B. Ent. 517, legend+text. • Rhamphomyia barbata: B. Ent. 517, text cont.. • Hemerodromia monostigma: 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.’.