Harlequin ladybird, Harmonia axyridis
Harlequin ladybird, Harmonia axyridis (submitted by NaturePlus user John)
The harlequins seen most often in the UK are orange with 15-21 black spots, or black with 2 or 4 orange or red spots. But there are over 100 colour and dot variants of this ladybird, making it hard to tell it apart from our native species. The key distinguishing feature is size. Natives are less than 5mm long whereas harlequins are bigger, around 7-8mm.
Originally from Asia, this beetle is an invasive species in the UK that has spread rapidly since it was first recorded in 2004. Where it has become established, the harlequin is often the most common ladybird species found.
Gardeners may welcome harlequins, as they eat a lot of aphids. However, this voracious predator easily out-competes our native ladybirds for greenfly and scale insects, and also eats the larvae of other ladybirds. Harlequins also appear to have another advantage, since they are the first ladybird species to emerge after winter in the UK and the last to hibernate.
Records show that they have caused several native UK ladybird species to decline.
