Malthodes marginatus (Latreille, 1806)
POLYPHAGA Emery, 1886
ELATEROIDEA Leach, 1815
MALTHININAE Kiesenwetter, 1852
MALTHODINI Böving & Craighead, 1931
Malthodes Kiesenwetter, 1852
Native to the Western Palaearctic region, this species has a rather patchy European distribution; in the south from northern Spain to Italy and Ukraine and to the north reaching the UK, Denmark and extending above the Arctic Circle in Fennoscandia, and the eastern extent of the distribution is parts of European Russia. Throughout this range it occurs from lowlands to middle mountain altitudes; in the Italian Alps reaching 2200 m. In the UK it is generally common throughout England and Wales and rather less so through Scotland north to Orkney and in Northern Ireland, in Southern Ireland it is very local and tends to be coastal. Typical habitats are woodland, wooded parkland and hedgerows but adults fly well and are likely to be encountered in any situation e.g. roadsides or domestic gardens, where broadleaf trees and shrubs are present. Adults are active from May until August, peaking in abundance during late May and June, although specimens have been found throughout the year, suggesting that pupation occurs both in late summer and spring. Mating pairs are easily found in the spring and early summer by sweeping low foliage, blossom or umbel flowers etc. They often occur in numbers and sometimes alongside other members of the genus. Flight-interception traps may also produce numbers of adults. Larvae develop through the summer under bark or among decaying wood; they are primarily predatory on saproxylic insect larvae but will also consume decaying wood as well as detritus including dead insects.
4.0-5.9 mm. Elongate and narrow with the head proportionally large, forebody black with the pronotal margins variably yellow, elytra dark brown with strongly contrasting yellow apices, appendages dark or with the femora and tibiae narrowly pale. Continental specimens are much more variable and here the anterior half of the head and the legs may be extensively pale. Head transverse with large convex eyes and long, curved and converging temples, vertex evenly convex to a transverse impression between the eyes, frons very finely punctured. The head varies in shape but in males it is wider than the pronotum and strongly narrowed to the base, in females it is about as wide as the pronotum and less strongly narrowed to the base. Mandibles smoothly sinuate internally, apical maxillary palpomere oval and pointed apically. Antennae long and slender, more so in males, second segment distinctly shorter than the third in both sexes. Pronotum transverse, lateral margins slightly sinuate and completely bordered, apical and basal margins curved and bordered, surface unevenly convex and with a median longitudinal impression. Elytra elongate, about 2.5:1 measured across the base, and more or less parallel-sided from rounded shoulders to separately curved apical margins which leave the abdomen and wings partly exposed, surface uneven-due to the soft cuticle-and finely punctured and pubescent throughout, without striae. Legs long and slender with femora and tibiae hardly widened from the base. Tarsi 5-segmented; the third segment narrowly lobed and partially concealing the fourth. Apical abdominal segments modified and distinctive in males, unmodified in females.
Malthodes marginatus 1
Malthodes marginatus 2