The 1mm long stingless Encarsia aleurochitonis lays its eggs in whitefly and devours its host. The wasp is known to live in mainland Europe, but may have been overlooked in the UK until now because of its size.
Dr Polaszek said since he first discovered the parasitic insect during a study of whitefly it had been identified in other parts of the country. He said: "It doesn't sting in the sense that it is absolutely no harm to people or children or pets or anything like that. It's got a tiny, tiny sting which it uses to lay inside the host.
"These animals perform an ecosystem service to us by controlling a lot of pest insects. The host, which is the whitefly, has been here since at least the early 1970s. It's such a small animal it could have been here a long time and simply been overlooked."
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