A group of ladybirds may be known as a “loveliness”, but there is nothing lovely about the Asian biting variety invading homes.
The non-native insect, originally from Japan and known as the harlequin or Asian beetle, has been seen swarming across the UK, from Cornwall to the North East of England.
The invasive species is putting smaller native ladybirds, such as the seven-spot ladybird, at risk by eating their larvae and competing for food sources such as pollen and nectar.
A homeowner from South Tyneside, Tyne and Wear, found his house infested by the beetles seeking warmth as the weather cooled.
“Absolutely inundated with those fake ladybirds,” he wrote on social media. “There are literally thousands all over my house.”
First found in the UK in 2004, the harlequin ladybird gathers in large groups and often hibernates inside homes over winter, unlike their native counterpart.
They are bigger than the native seven-spot ladybird and will bite humans, causing minor irritation and leaving a red mark, according to the Natural History Museum.
They also carry a sexually transmitted disease, called laboulbenia, which is a fungal infection that forms scales on the wings of ladybirds but cannot infect humans.
The population of several native British ladybird species has declined since the harlequin was first seen in Britain, according to research by the UK Centre for Ecology and Hydrology.
The recent arrival is “quite distinctive”, according to Max Barclay, senior curator of beetles at the Natural History Museum.
“You can find different varieties, from red with black spots, to orange ones, and even black ones with red spots,” he added.
“Whereas the native ladybirds are black on the underneath and have black legs, most of the harlequin ladybirds are orange on the underneath and have orange legs.”
A single adult harlequin can eat up to 50 aphids a day, and they were introduced to North America in 1916 to help protect crops.
From there they spread to Europe, and they have been increasingly seen in South America and Africa.
According to Mr Barclay, the insects would usually hibernate in caves, hollow trees and other sheltered places.
But they have been adapting to the urban environment and commonly infest houses over the winter.
They do not damage buildings, but their yellow defensive liquid can stain walls and furniture, according to the British Pest Control Association.
It recommends that harlequins, and other ladybirds, should be gently swept into a dustpan instead of being squashed.
Other pest control organisations suggest buying an electric fly killer to deal with infestations.
A dog walker from Sunderland said she was “attacked” by a plague of the insects while out walking, and a photo showed at least 20 crawling over her fleece.
Posting on social media, she wrote: “Has anyone else been attacked by the plague of ladybirds today! This is the craziest thing I’ve ever seen. I even had one on my face!”
A video shared on TikTok by one disgusted homeowner showed hundreds of harlequins covering the door frame of his house, while a resident of Newquay, Cornwall, shared a photo on social media showing large clusters of them covering her exterior wall.
A social media user from Wales said there were “hundreds” on her front door, with another complaining that her car was covered in them.
“I have never seen so many harlequin ladybirds,” wrote one poster. “Some of the gravestones were covered.”
Others complained of a “ridiculous number of ladybirds”, and that they had “literally never seen so many in [their] life”.