Oedemera virescens (Linnaeus, 1767)
POLYPHAGA Emery, 1886
TENEBRIONOIDEA Latreille, 1802
OEDEMERINAE Latreille, 1810
OEDEMERINI Latreille, 1810
Oedemera Olivier, 1789
Oedemera Olivier, 1789
This species occurs across most of the Palaearctic region, from Spain to the far east of Russia, China, Sakhalin and Japan, it is absent from most of Asia Minor and North Africa but has recently been recorded from Iran and is thought to be expanding its range. In Europe it is widespread and generally common in all but the highest mountain regions, it extends from Spain to Greece in the south and to the UK and all but the most northerly provinces of Fennoscandia. In the UK it is widespread but very local and, perhaps inexplicably, generally scarce; there are scattered records from South East and Northern England and Wales, and rather more from across Southern Scotland, but they tend to be common where they occur and, again, the species is thought to be expanding in range and abundance. Adults are active from March until August although specimens are occasionally recorded during January and February; they appear first on the earliest low flowers and then move on to blossom and a wide range of flowers, mostly various Apiaceae and Asteraceae where they feed on nectar and pollen. Reproduction begins early in the season following a period of feeding and proceeds into June or July. Females lay eggs low down on the stems of a wide range of herbaceous plants, and more specifically they have been observed ovipositing on species of Senecio L., Aconitum L., Helianthus L., Typha L. and Eupatorium L. Larvae initially mine the stems and work their way down into the root collar where they will continue to develop through the summer and then overwinter, they finish developing in the spring and pupate in situ during February or March. Typical habitats include densely vegetated grassland, heathland and scrub but they also occur on disturbed sites such as roadsides, railway embankments and parkland, and in northern Europe, where they seem to prefer yellow flowers, they often occur in open woodland and even domestic gardens. Finding adults relies on being able to recognize them in the field; they are superficially similar to the very common O. lurida but on average larger and more robust and, with experience, the swollen hind femora of males may become obvious.
6.5-11.0 mm. Body and appendages dull grey, sage-green or bluish-green, usually with a distinct metallic sheen, dorsal surface finely pubescent throughout. Head strongly produced in front of convex and protruding eyes, temples long and converging, surface finely punctured and rugose; in males often depressed along the centre. Antennae inserted in front of the eyes, 11-segmented, the second segment short, the rest long and slender. Pronotum quadrate or nearly so, broadest behind a curved apical margin and constricted before acute posterior angles, surface rugose throughout and in places with confluent punctures, anteriorly convex either side of the middle, towards the base evenly convex or slightly depressed. Elytra broadest across rounded shoulders and narrowed to separately curved apical margins, sutural margins often diverging towards the apex, each with three almost complete raised carinae and an abbreviated carina in the basal half, surface finely rugose and punctured throughout. Legs long and slender in females, front and middle legs long and slender in males, hind legs strongly developed; the femora and always much broader than the middle femora and the tibiae are curved and have a distinct external tubercle at the base. Tarsi 5-5-4, in each case the basal segment is very long and the penultimate segment strongly bilobed. Claws smooth and without a basal tooth.
Males are easily distinguished from lurida by the dilated hind femora, these may be weakly developed but are always much broader than the middle femora. Females may be distinguished by the form of the apical abdominal sternite (view from below and ignore the tergites), in lurida it is smoothly rounded apically while in the present species it is shallowly emarginate.