Harpalus rufipes (De Geer, 1774)
This very widespread and generally common species occurs throughout Europe, North Africa and through the Middle East and Asia Minor to the far east of Russia and Japan, and is also widely established in North America since being introduced sometime prior to 1937. Here it is locally common throughout England and Wales including Scilly, Man, Anglesey and the Isle of Wight, though less so and more sporadic in the north and many western records are coastal including those from the Scottish Islands. Adults occur year-round in a range of open and dry habitats including parks, gardens, wasteland, grassland and moorland and they are often abundant on agricultural land, they tend to overwinter in sheltered marginal habitats such as hedgerows or headlands and move to open habitats or among crops in the spring. Both adults and larvae feed on various seeds, the larvae exclusively so but adults are omnivorous and predate a range of insects, mostly aphids but they have been observed consuming both adult and larval Sitona weevils. They will consume a wide range of seeds, primarily those of grasses and various weeds such as fat-hen, but on the continent where they are abundant in conifer plantations they also consume seeds of larch, pine and spruce. They are nocturnal and can fly though rarely seem to but occasionally come to light or enter houses in the summer. In the past they have been a serious pest of strawberries and raspberries, adults consume the seeds and in doing so damage the fruit and leave it ruined but larvae seem to ignore fruits completely. New generation adults begin to appear from early summer, joining those from the previous generation that have overwintered and so they usually become abundant from the end of June and remain so into the autumn, these freshly-emerged specimens will begin maturation feeding although many will then enter into diapause during the warmest periods, and mating continues through the summer. Females oviposit during August and September; eggs are laid singly or in small groups in the soil or near plants in sparsely-vegetated
Harpalus rufipes 1
Harpalus rufipes 2
areas and each will lay between ten and fifteen eggs. Larvae emerge within a week or two and begin feeding on fallen seeds on the surface but as they grow they dig a burrow into the soil and provision it with seeds, first and second instar larvae continue this behaviour into late summer or autumn but the third, and final, instar will remain in the burrow feeding on stored seeds and developing through the winter, in early spring it will emerge and continue to feed on fallen seeds. Fully-grown larvae return to the soil to construct a pupal chamber between 15 and 45cm below the surface during June or July and new-generation adults eclose after about three weeks. Mortality is high in the summer and after breeding only about thirty percent will survive and go on to overwinter. The easiest way to record this species is by searching at night on parkland pathways or sparsely vegetated areas, adults are very active from dusk and easily observed and identified in the field, they often occur in numbers and usually alongside other common carabids. The best identification guide is the dull and pubescent elytra contrasting with the shiny black forebody and red appendages, with a little experience they become obvious.
11-16mm. A large elongate and broadly-oval species, entirely black but for the pale pronotal margins, interocular maculae and appendages. Head shiny and smooth or finely and obscurely wrinkled, eyes convex and prominent, each with a single supra-orbital setiferous puncture, mandibles robust and strongly curved before sharply-acute tips. Antennae rather short, finely and densely pubescent from the fourth segment. Pronotum evenly curved laterally then weakly sinuate before sharp posterior angles, surface shiny and rugose; narrowly pubescent along the basal and lateral margins. Elytra strongly bordered across the base and sinuate before the apex, each with nine well-impressed striae and weakly convex and densely punctured and golden- pubescent interstices. Legs long and robust, all tibiae with a long apical spur, on the hind tibia almost as long as the first tarsomere. Tarsi finely pubescent above, male with the basal pro-and meso-tarsomeres dilated. Our two species of Pseudoophonus are recognized by the combination of pubescent tarsi and entirely pubescent elytra, larger species of Ophonus are distinguished by the punctured and pubescent head and pronotum.