Dolichus halensis (Schaller, 1783)

This widespread species is generally common and often abundant across eastern parts of the Palaearctic region, including China, South Korea and Japan, but more local and sporadic in the west; it is locally common in central and eastern Europe but very local in northern regions where it has declined drastically over recent decades; there are old records from northern Germany, Denmark and the extreme south of Sweden but in many of these areas it is now considered extinct e.g. the last record from the Netherlands was from 1938. It does not occur in the UK. In Europe the typical habitats are open and rather dry grassland, arable land and open woodland, often on clay soils and floodplains, and sometimes on disturbed sites such as brick pits and even in urban landscapes. Adults are diurnal and very active on the soil surface in warm weather, they run fast and often climb grass stems in the afternoon, they have been observed to fly although through much of the eastern distribution it is considered a flightless species. Adults occur over a long season from late spring until the autumn and at least part of the population may overwinter, they usually occur in small numbers but are sometimes abundant in arable fields after the harvest and may aggregate within or under accumulated plant debris. Reproduction occurs in the autumn and larvae probably develop through the winter and pupate in the spring. In Europe the species occasionally disperses widely and may occur in new habitats or at sites from which it has long been absent but it is highly unlikely to occur in the UK; it is not known from Belgium and in Switzerland is known only from the south, it is very local and rare in northern France but occurs continuously from Alsace-Lorraine to the Pyrenees, and in Spain it is known from only two of the twenty three regions.

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​13-19 mm.  This impressive ground beetle may be distinguished by the overall form and colour, the forebody and elytra in front of the basal bead are shiny while the rest of the elytra are dull due to dense microsculpture. Head black or dark grey, usually with the anterior margin and two spots on the vertex pale brown, pronotum black with pale lateral borders, scutellum black, elytra typically dark grey or bluish-grey with the basal half (at least) pale red broadly red or reddish-brown from the suture although this is very variable and entirely dark specimens occur, appendages pale brown. Head with two setiferous punctures beside convex and protruding eyes, mandibles sharp and produced forwards, antennae and palps long and slender. Pronotum transverse, broadest in front of the middle and narrowed to rounded posterior angles and slightly protruding anterior angles, surface finely uneven and very finely punctured anteriorly but roughly sculptured across wide and shallow basal fovea. Elytra elongate-oval and broadest behind the middle, evenly curved from rounded shoulders to weak but distinct subapical constriction, striae narrow and finely punctured, the eighth narrowly impressed and in places represented by a series of setiferous punctures, interstices flat or weakly convex only towards the apex, the third with several (usually two) setiferous punctures close to the second stria. Legs long and slender, the front tibiae with a deep antennae-cleaning notch and all with a strong spur on the inner apical angle, tarsi 5-segmented, the basal pro-tarsal segments dilated in the male. Claws finely pectinate.