Atomaria lewisi Reitter, 1877

This species is native to the eastern Palaearctic and Oriental regions; it is generally common through central Asia to the far east of Russia, China, Japan and Korea and extends south into Northern India, it was first recorded from the west in the 1930s when specimens were found in a domestic garden in south east London and since that time it has spread through much of central and eastern Europe, extending north beyond the Arctic Circle in Fennoscandia. During the 20th century it also became established in the United States and Canada, where it now seems to be widespread, although it has only relatively recently been recognized as such, having previously been known as A. curtula Casey, 1900. Beyond this the species is sporadically recorded throughout the world, it is sometimes described as cosmopolitan but as yet seems to be established only in the northern hemisphere. In the UK it is now abundant throughout England and Wales but more local further north and in Ireland; it occurs on all the islands north to Shetland and is among our most common species of the family. Adults occur year-round; they overwinter among decaying organic material or in tussocks etc. and are active over a long season from early in the year, peaking in abundance from July until September. The species is widely eurytopic, living among decaying plant material almost anywhere; it is often common on open grassland and moorland and has been recorded from old bird and mammal nests, it occurs among garden compost and decaying straw and hay and may be common around stables and sheds etc, as well as other disturbed sites such as parks and domestic gardens. In northern regions, including the United States and Canada, it often occurs in wetlands and all types of both open and dense woodland. Adults are easily sampled by general sweeping or working through suitable samples of compost, and here accumulated grass cuttings can be very productive, they sometimes occur in numbers on hawthorn blossom and other flowers and they fly well, sometimes swarming on warm summer evenings and often coming to light or flight-interception traps.