Aulonothroscus brevicollis (de Bonvouloir, 1859)
This is a mainly southern and central European species; the distribution extends from the Mediterranean north into the UK, Belgium and southern Fennoscandia, and east into Asia Minor and Russia as far as Moscow, it is primarily a lowland species and over most of this range it is very local and generally scarce. In the UK it is widespread but very local across southern England although largely absent from the West Country, typical habitats are broadleaf woodland and wooded parkland and pasture where they are associated with a range of trees including lime and various Poplars but often Oak; they are often, but by no means always, associated with ancient woodland but any wooded habitat with plenty of older trees is worth investigating and on the continent they are often associated with disturbed habitats and newly planted woodland. Adults are active from April until October and peak in abundance during May and June, they are diurnal and probably nocturnal as well, and they often occur on low foliage or vegetation around the base of trees and in warm weather sometimes visit umbels and other flowers where they feed on pollen. Little is known of the biology but larvae have been found under bark and among decaying wood etc but also in tussocks and soil infested with fungi and their frequent appearance in soil traps in Europe might suggest they are more generally terricolous, feeding on or within fungi associated with decaying roots and soil detritus. Adults may be swept from flowers and vegetation, especially around trees where they developed as larvae, they may also occur in flight interception and sticky traps and with careful observation may be found on bark; our two records are from local deciduous woodland where adults were found on beech (Fagus sylvatica L.) by searching at night.
Aulonothroscus brevicollis 1
Aulonothroscus brevicollis 2
Aulonothroscus brevicollis 3
© Lech Borowiec
2.5-3.5 mm. Very similar to species of Trixagus Kugelann, 1794 and formerly included in that genus but distinguished by the form of the eyes which are entire or nearly so; the anterior margin may be sinuate or shallowly emarginate but is not deeply incised as in Trixagus. Easily recognized by the fusiform body and clubbed antennae, entirely dark brown and finely pubescent with paler brown appendages. Head hypognathous and only narrowly visible from above, eyes weakly convex and frons with a longitudinal carina close to the eyes, these may not be obvious but soon become apparent when the specimen is moved under strong light, surface otherwise evenly convex and finely and rather sparsely punctured throughout. Antennae 11-segmented; tow basal segments large and quadrate, 3-8 transverse and 9-11 form a compact asymmetric club. Pronotum widely transverse, broadest close to produced posterior angles and narrowed to a rounded anterior margin, surface evenly convex and finely punctured throughout; without sculpture although it may be weakly depressed in front of the strongly bisinuate basal margin. Scutellum triangular with curved lateral margins. Elytra with rounded shoulders and a continuously curved apical margin, striae deeply impressed near the base, narrow and finely punctured to the apex where they include a few much larger punctures, interstices flat or weakly convex, very finely punctured and with one or two variously-developed rows of larger punctures. Legs short and slender, femora simple, tibiae without apical spurs, tarsi 5-segmented and simple, claws smooth and without a basal tooth.