|Dromius quadrimaculatus (Linnaeus, 1758)|
|A common species occurring throughout England and Wales but, with the exception of the Isle of Wight,
there are no records from the islands. There are a few records from across central Scotland eg Ayr, Argyll, otherwise it
has an eastern distribution north to Easter Ross (luff).
Generally associated with deciduous trees and also pine (Lindroth)
in woodland, wooded pasture and parkland, gardens etc. The predacious adults fly and during the summer are likely to be
found in just about any situation; we have swept them from long grass in Cassiobury park (June-August 2006), from riverside
vegetation in Oxhey park (May 2006), from among reeds in Radlett road (August 2007) and recorded them at MV through the
summer in town centre gardens. The species is common across our Watford area and adults occur throughout the year, they
overwinter among grass tussocks, vegetation or under bark on logs or at the base of trees, and are summer breeders (Luff, ibid).
Larvae are predaceous, generally developing beneath bark but may also feed on exposed surfaces. Adults are known to feed on mites and springtails etc. on the bark surface (Alexander).
This elongate, flattened and charateristically marked species is distinctive although two other maculate carabids are similar; Philorhizus quadrisignatus (Dejean) is much smaller at 3.5-4mm while in Calodromius spilotus (Illiger)the elytral apices, beyond a preapical pale macula, are dark.
5-6mm. Head black with clypeus and labrum testaceous, finely punctured and somewhat shiny, eyes convex and protruding, temples glabrous and narrowed to base. Two setiferous punctures besideinner margin of eyes. Antennae pale, finely and densely pubescent from fourth segment, first segment shorter than second and third together. Terminal segment of maxillary palps longer and a little broader than penultimate. Pronotum shiny red or orange and distinctly narrower than elytra, front and hind angles rounded, front and hind margins straight, lateral margin rounded anteriorly and more or less straight in basal half. Finely bordered laterally and explanate towards base. Scutellum red, dull due to microsculpture. Elytra glabrous and flattened, gently sinuate laterally near middle and broadest near apex, apex truncate and weakly sinuate leaving terminal abdominal segment exposed. Outside margin finely bordered from sutural apex to scutellum. Surface shiny with microsculpture just visible at X20, striae well developed pale macula which are variable in size, the posterior of which occupies the elytral apex. Legs entirely testaceous. Tibiae without spines on outer edge. Foretibiae deeply notched inside. Tarsi without bilobed segment. Claws well developed, denticulate.
Description from 6 Watford species at X20.
Update - March 2009
Several specimens were recorded under pine bark in Whippendell wood.