Atomaria mesomela (Herbst, 1792)

Widespread across the Palaearctic region, but in Europe a mostly central and northern species it is locally common from northern parts of Spain and Italy to Ukraine in the south and reaching north into the UK and southern provinces of Fennoscandia although there are a few records further north to the Arctic Circle, it is generally absent from the Mediterranean islands and North Africa but it does occur in the Canaries. There are also records from California which if correct seem to represent the only North American site for the species. In the UK it is widespread and locally common throughout Southern and Central England and Wales, including all the islands, although it tends to be mainly coastal in the West Country and much of Wales, and extends north into southern Scotland where it is very local and generally scarce. Also widespread in Ireland though very local and mostly coastal or near coastal. This is essentially a wetland species; adults often occur among damp layered leaf-litter and tussocks in marshes or about the edges of ponds and rivers and sometimes in old reed or rush stems, they usually occur in numbers and may swarm in late spring or early summer. In Northern Europe they are recorded from all types of wetlands, including peat bogs and also occur in damp meadows and among accumulated organic matter such as grass clippings in damp situations, including domestic gardens. Adults are present year-round although they are rarely recorded in the winter; they are active from April until October and peak in abundance during June and July. This is among the most common and widespread of our hygrophilous species but little is known of the biology. Adults may be found at any time by sieving or extracting suitable material and they sometimes occur among flood-refuse. So far as is known adults are consistently short-winged.