A short guide to some of the black ladybirds you could encounter while ladybird spotting across the UK.
Britain is home to some 26 species of conspicuous ladybird. Far from your storybook red ladybird, many of these species are black in colour. Whether we’re talking about black ladybirds with red spots or melanistic (black) forms of familiar species, the similarities between these can be confusing. Below, you’ll find a little more information on some of Britain’s black ladybirds…
Identifying black ladybirds

Harlequin Ladybird, Harmonia axyridis
Probably the commonest of the UK’s black ladybirds, the Harlequin Ladybird is incredibly variable. Both the Conspicua and Spectabilis forms of this large invader are black in colour, albeit with differing patterns of red spots.
In general, Harlequin Ladybirds are large and domed in shape. While size is a good indicator, the best way to separate this from other species is by the markings on the pronotum (the area behind the head). Harlequins usually sport two conspicuous white patches on either side. Melanistic 10-Spot and Hieroglyphic ladybirds also have these, albeit to a lesser extent.
If your ladybird is exceptionally obliging, you’ll also notice that the legs of this species are brown.

Pine Ladybird, Exochomus quadripustulatus
The Pine Ladybird is a small species sporting four red spots, two of which are distinctively comma-shaped. Positioned towards the front of each wing case, these are the best way to separate this species from other black ladybirds.
In contrast to the Harlequin which shows a variable amount of white on the pronotum, that of the Pine Ladybird is entirely black.
Another good feature to look for is the pie-like rim around the outside of the wing cases. This feature is shared only by species within the same family and helps narrow down your choices.

Kidney-Spot Ladybird, Chilocorus renipustulatus
The Kidney-spot Ladybird looks a lot like the Pine Ladybird to which it is closely related. It shares the same domed shape, pie-like rim around the wing cases and black pronotum.
Kidney-spot Ladybirds are best identified by their large, red and parallel spots. One on each wing case. The only other ladybird boasting a similar pattern is the Harlequin; though these have white on the pronotum and brown legs.
This species is a bit more particular in its habitat choice and prefers deciduous woodland. It is often spotted on the trunks of willow or Ash in spring.

10-Spot Ladybird, Adalia decempunctata
The 10-spot Ladybird is perhaps the most variable ladybird in Britain. With dozens of colour forms, they can look like any other British ladybird, at least at first glance.
The chequered decempustulata form of the 10-spot Ladybird is black with a grid-like pattern of red or orange markings. Unlike many other black ladybirds, its legs are orange in colour and the pronotum features an extensive area of white. A melanistic form, lacking these features, also exists.
10-spot Ladybird is a generalist species and can be encountered in a diverse range of habitats. They are one of the ladybirds most often spotted in urban areas.

2-Spot Ladybird, Adalia bipunctata
Just to confuse things further, like the 10-spot Ladybird, the familiar 2-spot Ladybird also comes in various dark forms. Most often, these will have either four or six red spots sat atop black wing cases.
The four-spot form of this species has elongated, sometimes rectangular, red spots at the front of the wing cases. The six-spot form has four red spots, as opposed to two, towards the rear of the wing cases.
Fun fact: black forms of 2-spot Ladybird are thought to be more common in Northern areas where the darker base colour helps them absorb more heat from the sun.

Heather Ladybird, Chilocorus bipustulatus
One of Britain’s scarcer or at least harder to come by black ladybirds. The Heather Ladybird is a specialist species favouring Heather plants, most often in an upland setting. It can also be found in lowland and coastal heaths and can turn up in gardens where it may occur on cypress trees.
Closely resembling the Kidney-spot and Pine Ladybirds in shape and jizz, what sets this species apart is the distinctive line of red markings on the elytra. This can be fused or divided and may look like a solid line or a line of spots.

Hieroglyphic Ladybird, Coccinella hieroglyphica
The typical form of the Hieroglyphic ladybird is unmistakable and wouldn’t usually fit into a like blog post like this. Unfortunately, however, a melanistic form of this species also exists!
Black Hieroglyphic Ladybirds lack any visible markings on the elytra but do possess a pair of small white marks on the pronotum. They also have black legs and sometimes, two small ‘wedge-shaped’ white markings where the pronotum meets the wing cases.
This is a scarcely recorded species most associated with the uplands, though they do turn up elsewhere from time to time. Black forms are uncommon but cannot be ruled out.
Excellent information many thanks👍🏻