Anchomenus dorsalis (Pontoppidan, 1763)
This is the most widespread species of the genus, occurring throughout North Africa, The Middle East, Europe north to Scandinavia and east to Russia and Afghanistan. It is common and often abundant throughout England, Wales and lowland Scotland. Adults typically occur on open land; grassland, wooded borders, hedgerows and especially arable land. They prefer moist conditions and so will be found under logs and stones etc, particularly on disturbed soil. In general they are fast moving nocturnal predators but may occasionally be active by day, especially during very warm spells, climbing nettles etc. and sometimes, especially in the spring and autumn, aggregating in large numbers. They breed in the spring and are active from the first warm spells until late into the autumn; in spring and autumn they migrate between open land and more sheltered sites on scrub or in woodland. In general the diet is mostly small slugs and, to a lesser extent, other insects and their larvae, and they will occasionally feed on seeds.
Among the U.K. fauna this species is unmistakable; the combination of size and dorsal colouration being unique. 8-9mm. An elongate and rather flattened species. The forebody is metallic green, the elytra bicoloured; orange with the suture and a large macula in the posterior half metallic green. The colour varies; in the U.K. specimens tend to be typical whereas very pale specimens occur in Europe and very dark ones in eastern parts of the range. Appendages pale or variously darkened apically. Head convex and finely punctured, with two setiferous punctures beside each eye. Pronotum cordate with obtuse front and hind angles, the base extensively punctured. Elytra evenly rounded and weakly sinuate subapically, with explanate side margins. Basal border complete to the well developed scutellum. Intercalary stria present. The surface is densely microsculptured, with nine well impressed and complete stria; the third and the eighth with a series of setiferous punctures. Epipleura not crossed. Male with basal pro-tarsal segments dilated.