Leistus montanus Stephens, 1827
A generally local and rare species occurring in temperate upland and mountain situations in southern and central Europe from the Pyrenees and Northern Spain to the Alps and Carpathians and north to the UK, it is also known from turkey and Syria but the distribution may not be continuous. Six subspecies are described of which the widespread ssp. rhaeticus Heer, 1837 extends from northern Italy into the U.K. Four others occur in Europe and often overlap while ssp. shilenkovi Farkac in Lobl & Smetana, 2003 occurs in Russia. In the UK it was formerly widespread in the north and regularly recorded in mountain areas of Scotland and the Lake District but there seems to have been a decline over recent decades and it is now very local and restricted to highland areas of North Wales, Northwest England and possibly the Northern and Western Scottish Highlands, Western Isles and Orkney. There are several older records from Ireland, mostly from near the west coast, but it has not been recorded there since the 1920’s. Adults occur in dry situations among tussocks, under stones or among scree at moderate to high altitudes although very occasionally they also occur in lowland situations, they tend to remain among debris accumulated under rocks or scree and so may be difficult to find, and for this reason it may be under recorded. They are active from March until October and peak in abundance during April/May and again during September and October. Breeding occurs in the autumn and females oviposit among tussocks etc, some of these adults will persist into the following spring but most will die off through the winter, larvae develop through the winter and will pupate in the ground during the following spring and produce late spring and early summer adults. Both adults and larvae are predatory and both are specialist springtail predators although they also take other small prey.
7-9.5mm, the dorsal surface is metallic blue or green, often with the pronotal and elytral margins pale red. Legs entirely pale to dark red with pale tarsi; generally at least the femora are darkened towards the extreme apex. Head shiny metallic; the frons in front of and beside the eyes with irregular punctures and wrinkles. Antennae entirely pale with the third segment almost as long as the fifth. Pronotum broadest in front of the middle, with wide and distinctly punctured explanate margins and a setiferous puncture inside the obtuse posterior angles. The lateral margins are rather evenly narrowed from the middle to the anterior angles and at most only very slightly sinuate before obtuse hind angles, and the epipleura are pale. Elytra rather slender, about twice as long as wide and only weakly curved, with well-impressed and strongly punctured striae and a small shoulder-tooth.
Generally larger (8-10.5mm)
Pronotum less transverse, epipleura metallic blue, as the pronotal surface.
Legs usually extensively dark brown.
Head with only fine wrinkles beside the eyes.