Grammoptera ruficornis (Fabricius, 1781)
POLYPHAGA Emery, 1886
CHRYSOMELOIDEA Latreille, 1802
LEPTURINAE Latreille, 1802
RHAGIINI Kirby, 1837
GRAMMOPTERA Audinet-Serville, 1835
Alosterna Mulsant, 1863 includes 6 Palaearctic species and is most diverse in the east, the type species, A. tabacicolor, is generally common throughout much of northern Asia and Europe, extending north into Southern Scandinavia and the U.K. Here it is common throughout England and Wales, and there are a few Scottish records extending north to the highlands. The typical habitat is open woodland and wooded parkland. Adults occur from April to August; they fly well and visit a range of flowers including Ranunculus, Rosa, Aruncus and various apiaceae, generally in wooded situations but sometimes beside parkland pathways etc. remote from trees. Beating Crataegus as it comes into blossom in early May will often produce adults in numbers and a little later in May they can be found mating on flowerheads of all kinds. Host plants include a range of deciduous trees but the most frequent is oak and there have been occasional records from Pine. Larvae develop through the summer in damp decaying twigs and small branches, producing narrow irregular galleries which often extend into the xylem. The fully-grown larvae pupate in galleries under the bark during April or May and adults eclose soon afterwards, emerging from the wood during warm spells.This is one of the most abundant longhorns throughout much of Europe from the Mediterranean north to Scandinavia and the UK and east to the Caucasus, Turkey and Russia. Here it is widely distributed and common throughout England and Wales and there are scattered records further north to Ayr. Typical habitats are wooded borders and parkland, hedgerows, scrub and gardens etc. where the adults become active from early to mid April; they feed on pollen and nectar, first on Blackthorn (Prunus spinosa) then a little later, and usually in abundance, on Hawthorne (Crataegus monogyna) blossom. From May they are common on a wide range of flowers, especially those of Rosa canina and various Apiaceae but also on Rubus, Sambucus and Ranunculus, and will be seen in flight on warm days. Mating occurs from early in the year and pairs will be seen among hawthorne blossom etc. in the beating tray, females oviposit from May and eggs are laid among the bark or in crevices on thin decaying branches, often
those infested with fungus, of a wide range of broadleaf trees including Crataegus, Aesculus, Prunus, Pyrus, Ilex, Populus, Hibiscus syriacus, Quercus, Salix, Ulmus and Corylus etc. and both larvae and pupae have been recorded from Picea abies. Larvae feed through the summer and winter just beneath the bark and when fully grown in the spring construct a pupal cell in the outer xylem or in the inner surface of the bark. Pupation occurs in early spring and adults eclose after 2 or 3 weeks. The life cycle is completed within a year.
This is generally our most common longhorn and will soon become familiar in the field, the bicoloured antennal segments being characteristic. 3-7mm Body entirely black, densely punctured and with pale silky or silvery pubescence. Head elongate and moderately inclined, with strongly constricted temples behind prominent eyes and long, slender antennae which are more robust and shorter in the female, the second antennomere is distinctly elongate and all are bicoloured (ssp. obscuricornis Kraatz, 1886 from Azerbaijan and Iran has entirely dark antennae). Palps pale testaceous and darkened towards the apex; terminal segment enlarged and obliquely truncate. Pronotum quadrate or nearly so and broadest at sharply produced posterior angles; lateral margin smooth and evenly curved to a rounded anterior margin, surface smoothly convex. Scutellum elongate-triangular; punctured and pubescent as the pronotum. Elytra very elongate, parallel-sided or weakly dilated towards the apex and separately rounded or weakly truncate apically, pubescence recumbent and oblique to the suture. Legs long and slender; femora bicoloured although they may be extensively pale or dark, tibiae bicoloured but the pro-tibiae tend to be extensively pale, each with a pair of small but well-developed apical spurs. Tarsi dark or pale towards the apex, basal meso- and meta-tarsomere very elongate.