The alien in my living room was black with red spots!
This dark form of Harlequin Ladybird visited my home during October. The phenomenon attracted the attention of BBC2’s Autumnwatch because hundreds of viewers reported seeing the ladybirds in their houses.
Towards the end of October I watched dozens buzz through and over the garden. Undeterred by bumping into windows, bushes and me, they seemed intent on travel and were not stopping to feed – so I reckon a mass migration is happening in the UK.
Where are they going to? How fast will their pattern of distribution across the British Isles change by 2010?
These alien invaders, said to have arrived in the UK during 2006 – are causing a stir. Lots of people are searching Google and the BBC website for ‘Harlequin Ladybird’ in response to the beetle’s appearance on the BBC2 Autumnwatch series and various 2009 press releases. It was also a boom year for Seven-spot Ladybird, teeming by the bucketload at Somerset during the summer of 2009. Ladybird swarm on BBC News…
Spot the difference
The Harlequin Ladybird (Harmonia axyridis) comes in many guises. In Britain, however, most of the colour forms are distinguishable from common native species, such as the Two-Spot Ladybird and the Seven-spot Ladybird, by three very visible clues:
- Harlequin Ladybird often has a rough trapezoid or ‘M’ shape on the pronotum.
- When it’s not black, the base colour of the larger Harlequin Ladybird is usually yellow or orange, rather than red.
- The Two-spot and Seven-spot Ladybird have black legs; while the Harlequin Ladybird has orange-brown legs.
Perhaps the British species most likely to be confused with Harlequin Ladybird are the Eyed Ladybird (Anatis ocellata) or the smaller Ten-spot Ladybird (Adalia 10-punctata) which have orange legs and bright colour patterns similar to some of the harlequin’s.
The pronotum on a ladybird is frequently mistaken for the head, which the beetle tucks away in times of danger. One of the misleading markings on ladybird beetles is the huge spots on each side of the pronotum which act as false ‘eyes’.