Pterostichus niger (Schaller, 1793)
Female	Common throughout England, Wales and Scotland, being especially so in the Hebrides, Orkneys and Shetland Isles. An insect of woodland, damp grassland and upland moors. Around Watford associated with damp woodland, not found among the many thousands of carabids examined from parkland and town centre pathways and pitfall traps during 2006. An autumn breeder found occasionally in Whippendell wood under damp logs or loose bark during the winter, sometimes in groups of up to a dozen. Large, 15-21mm. Completely black but for the pitchy red tibial spines and claws. Head with 2 setae by the inner margin of the eye, antennae without longitudinal keels above basal segment (cf.Poecilus cupreus (L.)). Pronotum distinctly shaped; straight from hind angles to middle, posterior margin straight. Lateral margin weakly broadened towards hind angle (cf. P. melanarius Ill.) and inner basal fovea produced forward. Elytra with 3 punctures adjoining third stria, all striae, including scutellary, deep with intervals strongly convex, the seventh without raised humeral carinae (cf. Abax). Tenth (outermost) interval as wide as ninth (cf. P. nigrita Pk.), epipleura crossed. Basal metatarsal segments keeled externally. May be mistaken for Abax in the field because of their similar size but with a little experience is seen to be more slender, it also tends to remain still while Abax is usually very active when exposed. P. melanarius overlaps in size but is more convex and (with a hand lens) the ninth interval is much wider than the tenth. P. niger is glabrous beneath the claw bearing tarsal segment while in P. melanarius they are setose. Description from 4 Watford specimens at X10
Female	Male
Female	Male
Female	Male
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