Carabus glabratus Paykull, 1790
This is a widespread central and northern European species occurring from northern and eastern France to northern Italy and Romania, east to the Urals and extending to the far north, above the Arctic Circle, in the north it is more generally an upland and mountain species, typical of boreal forest fauna although throughout the range it also occurs on lowland heaths, juniper scrubland, forests and moorland; in Lower Saxony it is restricted to ancient woodlands. It remains locally common in many areas, especially in northern and mountain regions, but has declined in recent decades and is now rare and very local e.g. in Denmark and in Poland it is protected by law. In the UK it is a northern species, most common across northern and western Scotland including the Western Isles and Orkney, but otherwise local and scarce, from north Wales, northern England, Man and northern and south-western Ireland. Adults occur year-round and are active from May until late summer; they are nocturnal predators but may also be active during the day, walking among moorland vegetation or across sphagnum bogs. They occur in permanently damp environments, among litter on heather moors, among peat bogs or in shaded woodland; on the continent they are sometimes common in dense, dark pine forests. The species is flightless and disperses by walking, breeding occurs in the spring and early summer and larvae develop through the summer producing new-generation adults late in the year. Of the three European subspecies only glabratus s.str. (=lapponicus Born, 1909) is widespread and extends north to the UK.
This large,22-30mm, and entirely dark species has very reduced elytral sculpture and so may be mistaken for a dark C. violaceus in the field but it is wider and more convex, most noticeably so between the pronotum and elytra. Dorsal surface black or with a weak metallic blue lustre, appendages entirely dark. Forebody finely wrinkled throughout. Terminal segment of labial palpi weakly broadened and truncate, penultimate segment with 2 setae on the inner margin (in C. violaceus and C. problematicus there are always more than 2 setae). Pronotum transverse, explanate and strongly rounded laterally before an almost straight and converging basal third, disc convex then flattened before the basal margin so that in lateral view the hind angles are on the same level. Elytra elongate-oval with narrow and abrupt explanate margins, sculpture fine and dense, consisting of small elongate and flat granules which become confluent in places and may form several obscure longitudinal lines.