British Insects: the Families of Diptera
British Insects: the Families of Diptera |
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Shore-flies.
Adult insects. Very small to small; robustly-built. Antennae 3 segmented (the third rounded); ‘modified’. Antennae aristate (and the second segment sometimes with a downwardly curving spine); the bristle dorsal (bare, or plumed only on its upper side). The second antennal segment not grooved. Ptilinal suture clearly defined. Ocelli present; 3. Eyes not meeting. Post-vertical orbital bristles absent. Mouthparts functional. The maxillary palps 1 segmented; porrect. Vibrissae present (but poorly developed and not distict from the other bristles around the mouth), or absent. Thorax without a continuous dorsal suture; without well defined posterior calli. Wings without a discal cell (i.e., confluent with the 2nd basal cell); without a sub-apical cell; without a closed anal cell. The costa with two breaks (near the humeral cross vein, and near the end of vein 1). Sub-costa apparent, or absent or only dubiously identifiable (weakly developed except basally); joining vein 1 well short of the costa (weakly developed, and confused distally with vein 1). Vein 6 present; falling short of the wing margin. Vein 7 absent; reaching the wing margin, or falling short of the wing margin. Wings with the lower calypter much reduced or absent; patterned (e.g., Ilythea), or unpatterned. Tibiae without a dorsal pre-apical bristle. Hind tibiae without strong bristles in the basal 4/5. Predatory (on other insects), or neither parasitic nor predatory (feeding on decaying matter or excrement).
Larvae and pupae. Larvae aquatic (mainly), or terrestrial; phytophagous (within stems and shoots, often of water plants), or saprophagous, or coprophagous, or predatory; acephalic. Pupa enclosed within a puparium.
Comments. Very small to small flies of very damp places, some coastal. Wings sometimes with dark markings.
Classification. Suborder Brachycera; Division Muscomorpha Schizophora Acalyptratae; Superfamily Ephydroidea.
British representation: Genera about 40; 142 species.
Illustrations: • Discocerina, Notiphila, Ochthera: Walker. • Ephydra, Hydrellia, Teichomyza: Walker. • Ilythea spilota Haliday in Curtis (Spotted-winged Ephydra: B. Ent. 413). • Ilythea spilota (detail: B. Ent. 413). • Ilythea spilota (dissections: B. Ent. 413). • Ilythea spilota (B. Ent. 413, legend+text). • Ilythea spilota (B. Ent. 413, text cont.).
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: 9th June 2008. http://delta-intkey.com’.
