British Insects: the Families of Diptera


L. Watson and M. J. Dallwitz


Including Neottiophilidae, Thyreophoridae.

Cheese-skippers, Nest-flies, etc.

Life style parasitic (sometimes blood-sucking in the larval stage), or non-parasitic (mostly); on when parasitic, birds.

Adult insects. Small; winged. The face in lateral view not deeply excavated between the antennae and the edge of the mouth. Antennae 3 segmented; ‘modified’; twice aristate (in the sense that the second segment has a short, erect anterior bristle, additional to the arista on the third); the arista (or bristles) dorsal (on the second and third segments). The second antennal segment not grooved. The second antennal segment when viewed from the outside normal, with no extension over the third. The third segment not elongated (short and rounded, the arista almost bare). Ptilinal suture clearly defined. Ocelli present; 3. Lower orbital bristles present, or absent. Post-vertical orbital bristles present; divergent. Mouthparts functional (proboscis short and thick). The maxillary palps well developed, 1 segmented; porrect. Vibrissae present. Thorax without a continuous dorsal suture; without well defined posterior calli. Wing venation complete, in the sense of exhibiting 1st and 2nd basal, anal and discal cells. Wings with a discal cell; without a sub-apical cell; with a closed anal cell. The anal cell short. The costa unbroken (rarely), or with one break (mostly, at the end of the sub-costa). Sub-costa apparent; reaching the costa independently of vein 1 (immediately after the costal break). Wings without a ‘vena spuria’. Wing vein 4 extending far beyond the end of the first basal cell. Wing vein 6 present; reaching the wing margin, or falling short of the wing margin (curved). Wing vein 7 absent. Wings with the lower calypter much reduced or absent. Tibiae without a dorsal pre-apical bristle. Hind tibiae with strong bristles in the basal 4/5 (?), or without strong bristles in the basal 4/5.

Larvae and pupae. The larvae terrestrial; saprophagous (in dead animal matter. Including the jumping ‘Cheese-skipper’, which damages cheese and other fatty foods), or parasitic (Neottiophilum); when parasitic, ectoparasitic (Neottiophilum inhabits birds’ nests and sucks the nestlings’ blood); acephalic. The pupae enclosed within a puparium.

Comments. Small, shining, black flies, often reflecting bluish. The males do not exhibit the deformed fore-legs common in the Sepsidae.

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

British representation. 13 species in Britain. Genera 12; Actenoptera, Allopiophila, Centrophlebomyia, Liopiophila, Mycetaulus, Neottiophilum, Parapiophila, Piophila, Prochyliza, Protopiophila, Pseudoseps, Stearibia.

Illustrations. • Piophila casei (Cheese-feeding Fly: B. Ent. 126). • Piophila casei (detail: B. Ent. 126). • Piophila casei (dissections: B. Ent. 126). • Piophila casei (B. Ent. 126, legend+text). • Piophila casei (text, cont.: B. Ent. 126).

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.’.