Previous Awards

View the images from our previous Award winners.

Cavefish embryo Moth wing scales Popliteal aneurysm Honeybee Adult male mosquito Foreleg of a male diving beetle Caterpillar proleg Zebrafish retina Blastocyst embryo Ruby-tailed wasp Cell division and gene expression in plants Wheat infected with ergot fungus Mouse retina Laparoscopy surgery Blood clot on a plaster

Ruby-tailed wasp

Spike Walker

Ruby-tailed wasp

Download this image from Wellcome Collection.

This photomicrograph shows an adult ruby-tailed wasp curled into a ball. Chrysis ignita is the most commonly observed of several species of the ruby-tailed wasp. The wasp was lit with two electronic flashes while imaging to highlight the natural iridescent colours on its body.

What is a ruby-tailed wasp?

The ruby-tailed wasp is a metallic-coloured wasp (from the order Hymenoptera, which includes many common flying insects such as hornets, honeybees, bumblebees, common wasps and wood ants). The front half of this wasp, comprising the head and thorax, has a shiny blue-green appearance that sometimes has a golden sheen. The rear half of the body, the abdomen, is a beautiful deep ruby-red colour, which gives it its name. The underside of the ruby-tailed wasp is concave, allowing it to roll into a protective ball if threatened. The sting is seen in this image protruding from the wasp's abdomen; although present, it is not functional and most species have no venom.

Where did it come from?

The ruby-tailed wasp is found throughout Britain. This particular specimen was discovered by Spike Walker himself: "One summer morning I saw several of them flying around under the kitchen window…but it was very hot weather and they were moving quickly, so I thought I had no chance of catching one." However, Spike was formerly a beekeeper, and knows how to handle insects. So when he spotted this wasp in the kitchen window he captured it, deciding it would make a wonderful subject for microscopy. Then, to have any chance of examining - let alone photographing - it, he needed to calm it down, so he placed it in his freezer for a few seconds, causing it to assume its characteristic defensive posture.