RES Handbook Vol 6 Part 3a. Hymenoptera - Bethyloidea (excluding Chrysididae)

The Chrysididae, which are familiar insects, seem at first sight very different from the other much rarer Bethyloidea but intermediate genera occur in the American and Indo-Australian faunas. The Bethylidae are small or moderate-sized insects, usually black and with the same number of antennal segments (12 or 13) in both sexes, whereas in typical aculeates the male usually has 13 and the female 12. The larvae mostly live as external parasites of coleopterous or less often lepidopterous larvae . No real nest is made but in Bethylus the female takes her stung and paralysed prey into a sheltered place or hollow stem, lays several eggs on th e prey and stands watch over them until after they have hatched. Some other Bethylidae show a limited amount of maternal care. Only three British species are at all common and three or four others are introduced species, found in warehouses.
J. F. Perkins
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