More on Harlequin Identification Harmonia axyridis

Red Harlequin Ladybirds
Harlequin Ladybird with no spots
Mixed pair of Harlequin Ladybirds
As we've seen on the preceding pages, Harlequin Ladybirds have a varied number of spots, no spots at all and black backgrounds with red markings, making it harder for the non-expert to identify. The "W" on the "pronotum" (thorax) is also variable.
Harlequin and seven-spot Ladybirds
Harlequin Ladybirds with seven-spot
Black Harlequin Ladybirds of different size
Usually, the Harlequin is a little larger than our native 7-spot ladybird (shown with Harlequin in first and second photos above), but sizes vary so that's not a reliable guide.
Underside of typical brown-legged Harlequin Ladybird
underside of newly-emerged Harlequin Ladybird
underside of coupled Harlequins - one with black thighs
The typical Harlequin has brown legs, as virtually all new arrivals did when they first invaded this country and as the underside of the adult and newly-emerged one shows. The underside of the coupled pair shows black thighs on the red ladybird and brown legs on the black ladybird.
Harlequin Ladybird with black legs
Harlequin Ladybirds with brown and black legs
Harlequin Ladybirds' undersides and legs
Some of the invaders are developing black legs, presumably to more closely mimic the natives, as the underside of these hibernating Harlequins shows, -- but they still have BROWN FEET. The centre photo above also shows the orange/yellow fluid the Harlequins dispense from their "knee" joints when distressed or under attack; it is said to be foul-tasting and mildly toxic. From experience I can confirm that it stains, especially when hundreds of the ladybirds congregate in autumn, following their pheromones, on the back of a south-facing, light-coloured wall as they do on the back of my house each year now, seeking entry inside to hibernate over the winter. (Like most ladybirds, they hibernate as adults.)
Harlequin Ladybirds with pound coin
Black Harlequin Ladybirds with millimetre tape
Harlequin Ladybirds in millimetres
More on sizes: red Harlequins with pound coin and black Harlequins with millimetre tape measue.
Harlequin Ladybird in flight
Black Harlequin Ladybirds in flight
Harlequin Ladybird wings
Wings and bodies (and brown and black legs).