Coproporus immigrans Schülke, 2007
A recent arrival in Europe; recognized by Schülke (2007) as distinct from C. colchicus Kraatz, 1858, which is native to Europe, while revising the genus, and named from type material from Denmark, Germany, Norway and Sweden. This species was probably already established in the 1990s and is now known to be widespread; it is recorded from Austria, the UK, Belgium, Denmark, Germany, the Netherlands, Norway, Sweden, the Czech Republic and Portugal, it tends to be very local and sporadic but seems to be spreading rapidly and so should be expected to occur much more widely. The origins are unknown but it may have originated from Australia. The species was first recorded from the UK from Surrey in 2004 and since that time has proved to be widespread across the south from Worcestershire to Nottinghamshire and West Norfolk. Adults have been found in compost, heaps of bark and wood chippings and among organic matter, often near to human habitation, and in marginal wetland situations although in the UK the typical habitat is among damp wood chippings. In Northern Europe they have been recorded in all months from June to November but it is likely that adults occur year-round. They fly well but swarming behaviour has not been recorded, and in Germany they have been recorded at light traps in dry sandy grassland. When sieved from samples they can run very fast. Usually waving and rotating the abdomen as they go, and are likely to take flight when alarmed.
Coproporus immigrans 1
Coproporus immigrans 2
2.2-2.8 mm. Fusiform and very convex, shiny and glabrous except for very fine hairs on the abdomen, forebody black or with obscure paler margins to the pronotum, elytra black or with paler margins, abdominal tergites black with pale apical margins, the apical tergites sometimes entirely pale, antennae and legs pale brown. Pronotum and elytra without erect setae, abdominal tergites each with a single strong seta on the lateral margin. Head smoothly convex and very finely punctured between small and slightly-protruding eyes and long temples, antennae inserted anteriorly outside the external margin of the mandibles, 11-segmented and gradually widened from fifth segment. Terminal maxillary palpomere elongate, smoothly curved laterally and longer than the penultimate segment. Pronotum transverse, broadest near widely-rounded posterior angles and narrowed to acute from above) and projecting anterior angles, surface smoothly convex throughout. Mesosternum with a fine median keel. Elytra transverse and weakly narrowed from rounded shoulders to separately-curved apical margins, lateral margins longitudinally impressed and epipleura reflexed and not visible from above, surface randomly and finely punctured throughout (more strongly so than the pronotum), in places uneven or with fine and short longitudinal impressions. Abdomen strongly tapering from the base, tergites finely punctured throughout and with very narrow lateral borders. Tarsi 5-segmented.