Sub-millimetre-sized wasp discovered in scientist's son's playground.
Museum wasp expert Dr Andrew Polaszek has identified a new species of tiny wasp living inside whiteflies on a tree in his son's playground in Sevenoaks, Kent.
The wasp is a parasitoid. While true parasites depend on other organisms their whole lives, parasitoids just lay their eggs in other organisms. The larvae of newly discovered wasp, named Encarsia harrisoni, are born inside whiteflies and eat their way out.
It was the whiteflies on a maple tree in the playground that alerted Dr Polaszek to the presence of the wasp:
'I noticed some of the whiteflies looked slightly different to the others so I took them to the laboratory. When I saw the wasp inside I knew it looked different to anything I'd seen before.'
Not a tourist
Dr Polaszek made the discovery five years ago, but there was a lot of work to do to define it as a new species. Even more surprising to Dr Polaszek is that the new species is native to the UK.
'I thought it might be a species from Northern Europe that had come over to the UK. I was really surprised when I realised it was native to the UK and was previously unknown. Finding an undiscovered insect in the rainforests of Borneo is relatively easy but the fauna of England is some of the most studied in the world so to find something new here is a real thrill, and makes it even closer to my heart.'
In those five years Dr Polaszek has been regularly collecting the new wasp, but has never found a male, suggesting that females can lay eggs without them. This is similar to other parasitoid wasps, such as the related Encarsia formosa.
What's in a name
The new species is named after local scientist Dr David Harrison, chairman of the Harrison Institute that promotes taxonomic research to support biodiversity studies and conservation. The institute is only a few hundred yards from the trees where Encarsia harrisoni was discovered.
Dr Harrison has a few species named after him, but finds the new wasp especially intriguing:
'I now have a flea, a bug, a sand cat and a wasp named after me, which is obviously quite an honour. Dr Polaszek's wasp is a particularly interesting one - it was found right here in Sevenoaks just a few hundred yards from my home.'