Ripiphoridae

One species in Britain, the wasp-nest beetle Metoecus paradoxus (L.).  A spectacular beetle, 10-12mm long, with a bright orange abdomen, orange side patches on the pronotum, huge feathered antennae and triangular wedge-shaped translucent elytra which do not entirely cover the flight wings.  Larvae are parasitic in wasp nests, traditionally said to be only found in subterranean nests but several modern records are from nests in roof spaces.  Eggs are laid in the autumn on rotting wood, and larvae hitch a lift on wasps which visit to collect wood scrapings.  Once back at the nest, the larva drops off and finds a part-grown wasp grub, which it parasitizes and eats before emerging as an adult in mid-summer.