Stilbum cyanurum (Forster, 1771)
Family: Chrysididae – Cuckoo Wasps.
Length: up to 20mm.
Adults on wing July to October (Alicante, Spain)
The vivid metallic colourings of the body, can vary considerably in different lighting. Because of the vivid colouring of chrysidids, (Hymenoptera Chrysididae) they are commonly known as, “Jewel or ruby-tailed” wasps.
Stilbum cyanurum, is a widespread species, found over most of Spain and further north into Brittany, France. Favouring warmer climates of North Africa, Afro-Tropical, Oriental and also the Australian Regions.
Adults feed on pollen and nectar, of various seasonal flowering plants.
Cuckoo wasps are parasitoids and are also cleptoparasites because they steal their hosts food, before killing them.
The adult female wasp will enter the nests of various mud-nesting solitary bees and wasps. If attacked, she will curl up in a ball for protection from the hosts stings, (she is covered in an impenetrable armoured exoskeleton). If successful she will lay each egg, into a cell, next or onto the hosts egg or larva; when her eggs hatch, the larvae will feed on the provisions meant for the hosts larvae. The cuckoo’s larva will eventually kill and consume the host within the cell.
Habitat: Mainly open, well sunlit scrub-lands, near to various mud-nesting wasp and bee nests.