It is not known when the wasp first arrived in the UK
A tiny wasp discovered in Kent is providing an "ecosystem service" by attacking a common pest.
Dr Andrew Polaszek, who works at the Natural History Museum in London, found the insect in school grounds near his home in Sevenoaks during the summer.
The 1mm (0.04in) long stingless Encarsia aleurochitonis lays its eggs in white fly 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 white fly it had been identified in other parts of the country.
"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," he said.
"These animals perform an ecosystem service to us by controlling a lot of pest insects."
He said they did not know when the wasps first arrived in the UK.
"The host, which is the white fly, has been here since at least the early 70s and possible earlier," he said.
"It's such a small animal it could have been here a long time and simply been overlooked."
Other types of stingless wasps are commercially available to horticulturalists, but this is the first time this species has been found in Britain.
The wasp was first discovered during a study of white fly