Red-flanked and Angle-spot (plus Ant-nest) Ladybirds Comparison
These species are not that similar but there is still confusion on the internet.
Angle-spot Ladybird is a resident species of grassland that has been well recorded by ecologists for decades.
Red-flanked Ladybird is a newly arrived species, now common in gardens in the SE of England, but it still has a reputation for being a scarce migrant.
Ant-nest Ladybird is a conspicuous ladybird, but has traditionally been treated as an honary inconspicuous species, i.e. ignored in field guides. It is associated with ants in grassland.
Roy and Brown (2018), published the number of records for each species from 1975-2015:
Angle-spot 282
Red-flanked 114
Ant-nest 77
My own records from 2010-2018 produce a different picture:
Red-flanked 154
Angle-spot 2
Ant-nest 2
There is a perception that Angle-spot is the only common species in this group and I have seen several photos of Red-flanked on the internet, where a discussion has taken place over identification and despite a conclusion that it looks more like Red-flanked, Angle-spot is the final conclusion based on this being the more likely species.
For some time I have been publishing photos of Red-flanked on the internet, with comments on how common they now are, to try to reverse this trend.
Red-flanked is a mostly black species with a triangular patch on each wing case. This reaches the sides of the wing case and extends to the underside edge (epipleuron).
Red area reaches outer edge of wing case
Red extends to underside edge of wing case
Angle-spot is similar but has an angular oval spot in a similar position but this does not reach the sides of the wing cases.
On the underside Angle-spot has a groove along the centre of the metasternum, a feature only shared with Schmidt's Ladybird.
Red area not reaching edge of wing case
Distinctive groove along centre of metasturnum
Ant-nest Ladybird is similar to these two but has four round spots.
In males the white face is diagnostic, and both species show distinctive white (or dirty yellow) cheeks.
Some Angle-spot Ladybirds can show an apparent white face on some photographs, although this effect is due to light reflecting of the white hairs on a black or fed face.
Male with pale face and cheeks
Female with indistinct pale cheeks
When searching for Angle-spot Ladybird images on the internet, it quickly becomes apparent that a lot of the images are of Ant-nest Ladybird.
Angle-spot often has four spots on continental specimens, though this form is absent or rare in the U.K. This could explain the confusion between these two species.