Agriotes acuminatus (Stephens, 1830)
This species is generally common across western and central Europe from Spain to Denmark and Latvia, and rather less so in the south where it extends sporadically east to Asia Minor and Ukraine, it has been recorded only very occasionally further north in the south of Sweden and Norway but is common and often abundant throughout England and Wales and is recorded further north, though very rarely, as far as the Scottish highlands. On the continent it occurs from lowlands to the alpine zone, mostly in open wooded areas or sheltered grassland, and at higher altitudes the season is a little later. In the UK adults are active from April until July, peaking in abundance during May and June when they may be found on umbels in very large numbers, typical habitats are fairly dry woodland margins, hedgerows and wooded parkland but as they become abundant they may occur in just about any situation including domestic gardens. They appear first on blossom, particularly on hawthorn, and soon move on to a wide range of herbaceous foliage and flowers, particularly on various Asteraceae and Apiaceae, where they consume tender foliage, pollen and nectar. Shaking umbel flowers over a tray may produce numerous adults as they tend to feed, mate and rest over night among the flowers, otherwise they will appear in the sweep net regularly when working grass or foliage in most situations. Females lay eggs into the ground around the base of herbaceous plants or shrubs or among dense grass and larvae develop in the ground, consuming tender roots through the summer and moving deeper in the autumn to overwinter. Larvae development continues in the spring and pupation occurs in a subterranean cell from February or March, adults appear in small numbers from early in the year but seem to appear in large numbers as soon as the hawthorn blossom appears. Although distinctive and easily sampled a few specimens should always be taken for examination as a few very similar species are also common in the same kinds of habitats.
Agriotes acuminatus 1
Agriotes acuminatus 2
Agriotes acuminatus 3
Agriotes acuminatus 4
6-8mm. Elongate-oval and almost continuous in outline, dorsal surface shiny and with fine pale recumbent pubescence throughout, head black, pronotum black with pale posterior angles (this is variable and sometimes the entire basal margin is broadly pale), elytra pale to dark brown with the base and sutural margins darker, appendages entirely pale. Head almost as broad as the anterior pronotal margin, smoothly and weakly convex and moderately densely punctured between weakly convex eyes, antennae filiform or weakly serrate, the second segment about the same length as the fourth. Pronotum quadrate (females) or slightly elongate (males) and broadest across sharply-produced posterior angles, sinuate laterally and rounded anteriorly, punctures usually a little finer and less dense than those on the head, surface evenly convex, the posterior projections bordered externally. Scutellum pentagonal, relatively large, and punctured as the pronotum. Elytra at least 2.8X longer than the pronotum, striae well-impressed and punctured to the apex, interstices finely rugose; each with two or three rows of fine punctures throughout. Claws smooth.