Chlaenius vestitus (Paykull, 1790)
Chlaeniellus is generally included as a subgenus of Chlaenius but is sometimes considered to be a distinct genus; it includes our four UK species as well as another seven in Europe but is retained here under Chlaenius in order to conform to our latest checklist. This is among the most widespread of the Western Palaearctic species it occurs throughout southern and central Europe, North Africa including Iran and Iraq, Asia Minor and extends east through Russia, Kazakhstan, Turkmenistan and Uzbekistan to central Siberia, in Europe it occurs from lowlands to about 700m from the Mediterranean to the UK and southwest Sweden, it is generally common in the south but much more local and sporadic further north. In the UK it is locally common southern England south of the Wash and in South Wales though mostly coastal in the West Country, and very local and scarce further north to Cumbria and in Ireland. Typical habitats are shaded wetland margins, often on heavy soils with abundant vegetation, but also bare gravelly lake margins, coastal dunes and springs and streams in wooded areas. Adults occur year-round, they overwinter among matted vegetation or under stones or debris, often around the base of trees or fences, and are active over a long season from early in the spring, they are mostly nocturnal and usually occur in numbers although solitary specimens often become active in bright sun on hot summer days. Mating occurs in the spring and the predatory larvae develop through the spring and summer, they are also mostly nocturnal but have been observed hunting on bare damp soil in bright sun. Pupation occurs in damp soil, often in dry river or lake margins, this stage lasts about two weeks and new-generation adults generally appear from August. Established populations tend to persist over many years but adults are fully-winged and there are many flight observations from the continent and so new sites may soon be colonized. Adults are easily found by searching among debris and vegetation in suitable habitats, they hide among cracked damp soil or under debris during the day but will run when disturbed and are easily spotted, they sometimes come to light traps and pitfall trapping will often produce the species but in these habitats can be otherwise very destructive and so is best avoided.
Chlaenius vestitus 1
Chlaenius vestitus 2
Chlaenius vestitus 3
This large and brightly coloured beetle is absolutely distinctive among our fauna and cannot be confused with any other species. 8.5-11.0 mm. Body metallic green or bluish-green with pale yellow margins to the elytra, appendages pale brown, pronotum and elytra finely pubescent throughout. Head sparsely and very finely punctured and with a single large setiferous puncture beside each eye, antennae densely pubescent from the fourth segment. Pronotum transverse, broadest in the apical half and narrowed and sinuate to sharp posterior angles, surface with a variable median longitudinal impression and distinct basal fovea, finely punctured throughout, often sparsely so on the disc and densely so around the margins. Elytra gradually broadened from rounded shoulders to beyond the middle, apical margin continuously curved and usually distinctly constricted, striae impressed and punctured almost to the apex, and interstices slightly convex and densely punctured throughout.
Generally smaller (8.8-10.4mm).
Elytra smooth, lacking pubescence and punctures.