Dendrophagus crenatus (Paykull, 1799)
POLYPHAGA Emery, 1886
CUCUJOIDEA Latreille, 1802
BRONTINAE Blanchard, 1845
DENDROPHAGUS Schönherr, 1809
Dendrophagus Schönherr, 1809 is a small Holarctic genus of three species; D. longicornis Reitter, 1889 is endemic to Japan, D. cygnaei Mannerheim, 1846 is widespread in the Nearctic region and D. crenatus is widespread though very local and generally confined to colder areas and mountain regions in the Palaearctic region. In Europe D. crenatus is very local and generally rare in central and northern areas with isolated populations in the Pyrenees, the Alps and other mountain regions, to the north it extends to the UK and above the Arctic Circle in Fennoscandia and Russia and to the east occurs extensively through the taiga zone. In Europe the species is associated with various conifers, especially spruce and pine, sometimes where these have been damaged by fire, and more rarely broadleaf trees while in the UK it is confined to primary pine forests in the Scottish Highlands below Inverness. Adults live among dry crumbling bark and are rarely encountered in the open, they occur in the spring and early summer when mating and oviposition takes place, the flattened pale-brown larvae develop under bark of broadleaf and conifer trees feeding on fungi, and new generation adults occur from August and are thought to overwinter under bark. Typical habitats must include plenty of older trees with areas of wood at an advanced stage of decay and females will only choose timber extensively invaded by fungi in which to oviposit.
6-7mm Elongate and discontinuous in outline, very depressed and coarsely punctured throughout, the only UK species with which it might be confused is the common Uleiota planatus (Linnaeus, 1761) but here the pronotum is transverse and toothed laterally and the dorsal surface is dull, in the present species the pronotum is elongate with smoothly sinuate lateral margins and the dorsal surface is shiny. Entirely chestnut-brown or with the forebody darker than the elytra, dorsal surface very finely pubescent throughout. Head transverse with convex protruding eyes and small, strongly converging temples, vertex longitudinally impressed either side of the centre and labrum produced anteriorly between broad, strongly curved and bidentate mandibles. Antennae inserted laterally in front of the eyes, scape long and gradually thickened to a truncate apex, second segment quadrate to slightly elongate, remainder strongly elongate. Pronotum broadest in the basal half, narrowed to obtuse posterior angles and sinuate to obtuse anterior angles, surface very finely microsculptured and densely but not confluently punctured. Scutellum widely transverse, broadest about the middle and curved apically, the surface punctured as the pronotum. Elytra elongate, about 2.5:1, with broad and slightly angled shoulders, broadest before a continuously-rounded apical margin and weakly explanate about the middle, each with eight punctured striae complete to the apex and an abbreviated stria or a confused area of punctures behind the scutellum. Legs pale brown, long and robust with clavate femora substantially visible in normal setting, slender tibiae only weakly broadened to rounded apices and slender five segmented tarsi.
Dendrophagus crenatus 1
© U.Schmidt 2006 https://www.kaefer-der-welt.de/index.htm
Dendrophagus crenatus 2
© Lech Borowiec http://www.cassidae.uni.wroc.pl/Colpolon/index.htm