Metopsia clypeata (Müller, P.W.J., 1821)
This Palaearctic species is restricted to western and central Europe and North West Africa, it is recorded from Algeria, Morocco and Tunisia and extends from Portugal to Austria in Europe, extending north to the UK and southern provinces of Fennoscandia, and it is locally common in lowland areas throughout the region but rarely occurs in numbers. In the UK it occurs throughout England and Wales although it is generally absent from the West Country, and is very local and sporadic further north to the Scottish Highlands. Adults are active from March until October, they occur among decaying organic matter in tussocks, leaf-litter, dung and fungi and have been recorded nocturnally at sap and under bark, especially in the vicinity of fungi, and in small mammal runs but during spring and summer they are active among vegetation and may occur by general sweeping, especially among long dry grass in open situations. Little is known of the biology but adults are thought to be mycophagous and most of our records are from spring/early summer and autumn; an interesting record is of adults we found among decaying hypogean fungus, along with many other beetles, unearthed from calcareous grassland on a south-facing hillside in South Buckinghamshire during September 2015. Our other records are from dung and from sweeping mixed herbage beside reed beds near Watford town centre, Herts.
2.5-3.0mm. Easily distinguished among our UK fauna by the structure of the head; the vertex has a single central ocellus and the anterior clypeal margin is widely emarginate. Elongate and rather parallel-sided, entirely pale brown or yellow, often with obscure darker areas, dorsal surface of forebody with deeply impressed punctures and small tubercles. Entire insect very finely pubescent. Head transverse with large convex eyes and converging temples, clypeus extended and angled in front of the eyes so covering the antennal insertion. Antennomeres 3-8 narrow and elongate, 9-11 a little broader, producing a gradual and often indistinct club. Pronotum widely transverse, broadest at perpendicular posterior angles and narrowed to rounded anterior angles, lateral margins irregular and the basal margin with a fine tooth towards the edge, surface with a wide median longitudinal impression. Elytra quadrate with narrowly raised and finely crenulate lateral margins, surface moderately strongly punctured and lacking striae. Abdomen finely punctured and pubescent throughout basal tergites with widely-raised lateral margins and last tergite produced apically. Posterior margin of sixth sternite with a deep triangular incision in the male. Legs long and slender; the middle and hind femora visible in normal setting, tibiae without apical spurs, the middle and hind tibiae with a series of small dark tubercles internally towards the apex. Tarsi 5-segmented, the basal segments finely lobed and the terminal segment long and curved, claws paired and simple.