Malachius bipustulatus - Female ID help
Within the Malachite beetles (Malachiidae) of Europe there are several species that are all bluish-green with red, orange or yellow tips of the elytra. The males can usually be distinguished by the position and shape of their excitators but the females can be very difficult to tell apart.
To properly recognize the female of the very common Malachius bipustulatus a close look at the antennae can be very helpful. The second and third antenna segments are much shorter than the 5th and the 4th is somewhat shorter still but also clearly wider "axe"-shaped (if seen under the right angle).
Also, on many specimen, the fore corners of the pronotum will be slightly reddish (as indicated by !! in the image), but be very aware that all species have reddish skin cushions/bladders just under the pronotum that can be inflated when excited - just barely recognizable in the image and indicated by the question mark. On mediocre images it is usually quite impossible to tell reliably if there is a red corner of the pronotum or not due to the cushion giving a red impression also. Compare this image of the same female where both can be barely told apart (and that is a fairly sharp image):
The antennae of the females of Cordylepherus and Clanoptilus are shaped differently, with the second segment being short but from the 3rd on longer and subequal in length.
(will add images for that later at some point)
''Malachius bipustulatus'', the malachite beetle, is a species of soft-winged flower beetles belonging to the family Melyridae subfamily Malachiinae.
The body is 5–7 millimetres long, the head and pronotum are brownish, while elytrae are shining metallic green with a bright red spot at the end. Along the sides of the abdomen this species has a peculiar structure with orange poaches.
These beetles mainly inhabit meadows at low altitudes. During the day they stay on herbs and.. more