Joseph’s coat of many colours. Among the most beautiful animals in the world, the Chrysididae make use of nature’s broad palette to paint the estimated 3000+ species in the family. No wonder that “jewel wasp” is one of the popular names for this family. They are also known as cuckoo wasps because many chrysidid species are cleptoparsitoids, their behaviour mimicking that of their avian namesakes. Cuckoo birds push another bird’s chicks (or eggs) out of the nest and lay their egg(s) in the now empty, ready-made nest she has invaded. The unsuspecting mother continues to forage for food that she brings back to the nest expecting to find her chicks awaiting her arrival. Instead, she sits atop the cuckoo’s egg and begins incubating it. Similarly (but leaving out the incubating bit), the female cuckoo wasp enters the occupied nest of a wasp or bee and deposits its egg(s) there. Upon hatching, the cuckoo wasp larva kills and eats the host’s larva (or egg) before eating the food provision for the host’s offspring.
Chrysididae are well-armed (one might say well armoured). The vast majority of chrysidid species have a very hard exoskeleton, its strength augmented by the field of punctures that cover it, fortifying it much like an egg carton protects its contents. Also, in jewel wasps of the subfamily Chrysidinae (which contains the vast majority of chrysidid species), the ventral surface of the abdomen is deeply concave. If attacked, the wasp merely rolls itself into a ball like an armadillo, waiting out the ineffectual attempts by the soon-discouraged predator to crack the integument.
Chrysididae have been around for a long time. The earliest known fossil of a jewel wasp is from the Aptian stage of the early Cretaceous, between 121 and 113 mya (million years ago).
The family Chrysididae was erected by the French entomologist Pierre André Latreille in 1802. We first encountered Latreille as the author of the beetle family Geotrupidae (see Insect of the Week [92]). Much earlier, in1761, Linnaeus authored the first species of the genus Chrysis which later gave its name to the family.
The specimen in today’s Insect of the Week was captured in a Malaise trap set in Mumoni forest, eastern Kenya.