The latest nonsense (The Daily Mirror for a change, which I won't dignify with a link) is that they are infected by a sexually transmitted fungal disease. It isn't nonsense that they have the disease, but the implication that they will somehow harm our native wildlife is nonsense. It is nonsense because different species cannot mate with each other. That is the definition of a species, and is especially true of insects which have hard chitin parts that must fit exactly for insemination to be achieved. There may be a danger of transmission by contact, but that's a contagious disease not an STD.
If you want to get excited about dangers to our native ladybirds then maybe we should worry about them feeding on aphids, that in turn feed on plants treated with neonicotinoids, or worse, plants that haven't been treated with neonics but are growing in soil contaminated by neonics which accumulates in the soil and stays there for many years.
As the following photos show, there is considerable variation in the colours and patterns of harlequin ladybirds (probably nominative determinism - why else would they be called harlequins?). The UK Ladybirds Survey website ( http://www.ladybird-survey.org/ladybirds.aspx - a great site for identification and ladybird information generally) says that harlequins are yellow-orange, orange-red, red or black with between 0 and 21 orange-red or black spots. No problem with identification there then! But the best way of being sure that it is a harlequin is to look for brown legs. Most of our other species have black legs.
No captions, every one a harlequin - Harmonia axyridis
