Insects of Britain and Ireland: the families of Hymenoptera
Adults small to large; 5–15 mm long. Solitary insects.
Head. Eyes ovate and not emarginate. Antennal segments (10–)12 (females), or (10–)13 (males). Antennae geniculate, or not geniculate.
Thorax. Thorax orange or black-and-orange. Thorax of the wingless females without distinct segmentation dorsally. Pronotum long, extending back to the tegulae. The spiracle cover lobe of the pronotum margined with close fine hairs. Mesopleuron without a suture. Cenchri absent. Wings present (males), or absent (the ant-like females); not folding longitudinally. Fore-wings with a conspicuous pterostigma; with the venation well developed. Closed fore-wing cells 6–10. Hind-wings with closed cells; of the males without a jugal lobe. Fore femur not noticeably dilated. Hind femur without a well defined trochantellus. Hind tibiae without specialised spurs.
Abdomen. The abdomen with a marked basal constriction; long petiolate to short-waisted. The waist simple. Visible abdominal segments 6 (females), or 7 (males). The gaster colour-patterned; black-and-white or black-and-yellow. Ovipositor of females not visibly protruding; modified as a retractable sting.
Larvae. Larvae legless or the legs vestigial; socially parasitic on hosts selected by the mother and predacious, or parasitic on hosts selected by the mother, or feeding on prey collected and stored by the adults (Mutilla europaea parasitizes Bombus species, while Smicromyrme rufipes parasitizes pompilids and sphecids).
General comments. By contrast with Tiphiidae, the hind-wings of the males are without a jugal lobe, and the thorax of the wingless females lacks distinct segmentation. The females are usually readily distinguishable from ants by a felt line on the second gastral segment.
British representation. Species in Britain 2; Mutilla and Smicromyrme.
Classification. Suborder Apocrita; Series Aculeata; Superfamily Scolioidea.
Illustrations. • Smicromyrme rufipes (B. Ent. 077). • Smicromyrme rufipes (details: B. Ent. 077). • Smicromyrme rufipes (dissection details: B. Ent. 077). • Smicromyrme rufipes (B. Ent. 077, legend+text). • Smicromyrme rufipes (text continued: B. Ent. 077). • Mutilla europaea: Saunders VII.
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’.