Pterostichus minor (Gyllenhal, 1827)
Common and sometimes abundant throughout England and Wales including the Isles of Wight, Lundy, Anglesey, and Man although records are sparse in the west country and become less frequent north of the Humber. There are scattered records from Scotland north to edinburgh, further north there are a few records from the Highlands, Islay and mainland Shetland (NBN june 09). Typical habitat is wetlands; among vegetation in marshes, carr and fens (Lott, 2003). Locally they occur rather sporadically among pond and riverside vegetation, usually as single specimens and often under debris, most of our records are from extractions of grass tussocks and leaf litter etc from likely habitats. They sometimes occur in pitfall traps and we have recorded them each summer between 2006 and 2009 from reed litter at Radlett road. The species is a spring breeder (Luff) and locally adults occur from March until August or September.

With experience minor can be distinguished in the field from other small dark wetland carabids; at X10 the form of the double basal fovea and external raised ridge are obvious.

6.8-7.9mm (Luff). Body entirely black without metallic lustre. Head smooth and shiny, frontal furrows weakly impressed to about front margin of eyes, without other impressions. Two setiferous punctures besides eyes. Mandibles sharp with smooth outer edge ie without punctures. Palps rufous, lighter towards apex; terminal segment of maxillary palps well developed, as long as penultimate. Penultimate segment of labial palps with two fine setae. Antennae variously darkened; rufous at least towards base, segments 1-3 glabrous and without keels, basal segment only slightly, if at all, longer than the third, 4-11 pubescent. Pronotum transverse (typically 4:5), widest in front of middle, sides smoothly rounded to behind middle then sinuate to sharp (but not toothed) hind angles. Side borders strongly impressed. Basal third or quarter strongly but sparsely punctate. Two basal foveae; the inner extending further forward and the outer delimited by a raised ridge inside side margin. Elytra black or ptchy brown and proportionately short, parallel sided and only weakly sinuate before apex. Striae (including scutellary) well impressed and only weakly punctured, usually with three dorsal punctures which are arranged symetrically. Interstices shiny and wekly irridescent. Epipleurs crossed before apex. Legs dark brown, usually lighter towards apex. Femora large and well developed, front tibiae with a strong subapical notch and a single large spur on inner side at apex. Basal segments of male front tarsi dilated. Claws smooth.

Description from 2 Watford specimens at X20.


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