Micropeplus fulvus Erichson, 1840
This locally common species occurs throughout southern and Western Europe and North Africa, extending north into southern Fennoscandia and the UK, it occurs from lowland to mountain altitudes (about 1500m in Turkey) and, though rare and sporadic in many northern areas, is generally one of the commonest members of the subfamily. Further east it extends far into Asia and in China, India and Japan is represented by the subspecies japonicus Sharp, 1874. Here it is widespread and locally common across England and Wales though very local and scattered in the north and sporadic and rare in Scotland north to the highlands, it is absent from the West Country and there are no records from the islands. Adults are present year-round and usually occur in numbers when found, typically among decaying vegetation such as hay or straw refuse and compost heaps but also in very moist marginal wetland situations e.g. we find them in abundance in extraction samples taken through the winter from piles of pond clearance in a local park. During the warmer months they may be sieved from compost, extracted from samples or, occasionally, swept from vegetation in damp and shaded habitats, they disperse during summer evenings, are attracted to light and regularly occur in flight-interception traps. Hinton (1941) reported finding both adults and larvae in a compost heap in Cambridgeshire during January; they occurred both among the compost and near ground level ‘among partly liquefied cabbage leaves and other plant refuse’, and a single pupa was found in a cell about an inch below the ground at the bottom of the heap. In Spain adults have been swept from crops in areas of cultivated cereals and legumes intended for forage, and in the south of Europe generally the species is also associated with woodland environments, occurring under bark of coniferous and broadleaf trees, among leaf-litter, under logs and among grass and moss on wooded margins. Both adults and larvae feed on plant material and moulds.
2.0mm. Elongate with the pronotum and abdomen wider than the rather parallel-sided elytra, pale to dark brown with the pronotal margins and appendages paler although specimens with dark antennae occur on the continent. Head transverse, rounded or weakly angled anteriorly in the female, produced in the male, with convex eyes and short, curved temples that are usually hidden under the pronotum. Vertex with five longitudinal furrows that converge anteriorly although these may be indistinct among a generally strong sculpture. Antennae pale; basal segment broad, 2-5 elongate, 6-8 quadrate to transverse and the terminal segment forming an abrupt club. Pronotum transverse, widest behind the middle and sinuate before strongly-produced anterior angles, disc with several wide impressions bound by raised carinae, laterally broadly explanate and finely punctured. Elytra transverse, each with 4 raised longitudinal ridges complete to the apex, between these with large and deep punctures loosely arranged into three rows, basal margin a little narrower then the pronotum between the posterior angles. Abdomen widely explanate and dilated compared with the elytra; three basal tergites with three longitudinal ridges joined across the apex of the segments, fourth segment with three abbreviated ridges; the central ridge ending about half way along the segment and in lateral view obtusely angled.