Stenurella melanura (Linnaeus, 1758)
A generally common and occasionally abundant species with many modern (post 1970) records throughout southern England, including the Isle of Wight, and the east midlands north to the humber. Absent from Wales and, with the exception of a few modern records from south Cumbria, the west of England above Birmingham (Twinn and Harding). Typical habitat is open woodland, wooded pasture, parkland etc and the adults occur between May and September. They fly readily in sunshine and visit a range of flowers and blossom; among those recorded are bramble, Euphorbia, dog rose, hawthorn, hemlock, hogweed, honeysuckle, ox-eye daisy, phaseolus, privet, rubus, scabious, thistles, tilea, viburnum and yarrow (Uhthoff-Kaufmann, 1988). Bily and Mehl quote 'flowers of Apinceae and Astaceae'. The species is polyphagous and recorded hosts include oak, beech and sycamore as well as various conifers eg picea, abies and pinus. Larvae bore longitudinal or undulating galleries in the sapwood of slender branches, trunks or decaying stumps, more especially in damp areas. Uhthoff-Kaufmann (loc cit) also records them from feeding in the roots of Cytissus. Pupation occurs in the outer sapwood and (at least in Denmark) the life cycle generally takes two years. We have yet to record the beetle from our Watford area, those figured were found running on oak logs near Brockenhurst, Hants (June 2009).

A small (6-10mm) longhorn, entirely black but for red elytral macula as shown. Dorsal pubescence black, abdominal sternites, meso and metanotum with pale grey pubescence. Male slender, female more robust.[Elytra with side margin narrowly black, in male reddish yellow with apex narrowly black, in female yellowish red with apex broadly black-Joy]. Head elongate and obliquely inclined forward, puncturation coarse and dense, generally confluent behind antennal insertions and with a smooth central line from base to labrum; labrum sparsely punctured. Eyes convex; oval in side view and with a wide and deep incision to the upper edge (to accommodate antennae when raised over the head), temples hardly discernable; head constricted behind eyes to neck. Second antennal segment short and quadrate, remainder elongate. Pronotum slightly elongate; campanulate and without lateral sculpture or margins. Anterior and posterior margins bordered; posterior margin bisinuate between sharp and obliquely protruding hind angles. Puncturation dense and even, surface weakly depressed in front of hind margin; not furrowed. Elytra tapering tp apex; in the male about 2.5X longer than wide, in the female about 2.2 times. Apices incurved, sutural angle obtuse or weakly produced, outer angle weakly produced into a spine. Colour generally as shown but varies; in the female to almost entirely black (Bily and Mehl). Legs long and slender; femora weakly clavate, tibiae without teeth but with two strong spines at apex, in our specimens these spines (and the claws) are testaceous. Basal segment of metatarsi longer than remainder combined. Claws smooth and weakly curved, with a weak tooth at base.

Our other species of Stenurella, S.niger (L.) is a local and rare species of southern England. Here the elytra are completely dark, the abdominal sternites are orange (in melanura they are black) and the pronotal puncturation is sparse and fine.

Description from 2 south Hampshire Specimens at X20.


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