Insects of Britain and Ireland: the families of Hymenoptera
Chalcid Flies, Chalcid Wasps.
Adults minute to small; (0.6–)1–4(–10) mm long. Insects associated with plant galls, or not associated with galls.
Head. Antennae geniculate.
Thorax. Pronotum more or less straight at the back; short, not extending back to the tegulae. The mesepisternum not enlarged to obscure the mesepimeron (and the mid-tibial spur rarely larger than the hind one). Cenchri absent. The wings marginally very long-fringed (sometimes?), or not long-fringed; wings folded longitudinally when at rest (Leucospidinae), or not folding longitudinally. Fore-wings without a pterostigma; with very reduced venation (reduced to a proximal submarginal vein, which becomes marginal distally before giving off the stigmal vein); combining greatly reduced venation with a conspicuous, blind-ending stigmal vein. Closed fore-wing cells 0. Submarginal cells 0. Discoidal cells 0. Hind-wings without closed cells. The hind coxae five to six times the size of the front ones. Fore tibiae with a curved spur. Hind femur toothed below (and enlarged); with a clear trochantellus. Hind femur with a row of teeth beneath. Hind tibiae nearly always conspicuously curved around the femora; without specialised spurs. Tarsi 5 segmented.
Abdomen. The abdomen with a marked basal constriction. Ovipositor of females visibly protruding; adapted for piercing.
Larvae. Larvae with segmented legs; (mainly or exclusively?) parasitic on hosts selected by the mother (especially on Diptera and Lepidoptera, but also other insect orders), or predacious (?); when associated with galls, parasitic on other gall occupants, or predacious on other gall occupants.
General comments. The hind femur enlarged, and toothed below.
British representation. Species in Britain about 6; Brachymeria, Chalcis, Haltichella, Spilochalcis.
Classification. Suborder Apocrita; Series Parasitica; Superfamily Chalcidoidea.
Illustrations. • Chalcis biguttata (Essex Chalcis: B. Ent. 472). • Chalcis biguttata (detail: B. Ent. 472). • Chalcis biguttata (dissections: B. Ent. 472). • Chalcis biguttata: B. Ent. 472, legend+text. • Chalcis biguttata: B. Ent. 472, text cont.. • Haltichella rufipes: as H. armata, 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. Insects of Britain and Ireland: the families of Hymenoptera. Version: 16th May 2016. delta-intkey.com’.