Cramp-ball fungus weevil

Appearance

Elongate and discontinuous in outline with a ‘lumpy’ appearance, black or reddish-brown with dense recumbent pubescence; extensively pale to the head, rostrum and elytral apices but forming cryptic patterns on the elytra.

Head, including rostrum, parallel-sided and slightly elongate with small, convex and prominent eyes and a deep median longitudinal impression. Antennae short and slender with an abrupt 3-segmented club, inserted laterally about mid way along the rostrum. Pronotum transverse, angled laterally and constricted before sharp anterior angles, surface rugose and coarsely punctured; before the base with an incomplete transverse keel.

Elytra parallel-sided, with broad and well-defined shoulders and evenly curved to continuously rounded and narrowly explanate apices, striae narrow and consisting of series of shiny punctures which stand out among the dense scales, interstices broad and mostly flat; colour and pattern vary but there are usually series of transverse pale and dark bands, extensively pale apices and several pale markings along the base. Legs robust and rather long, femora and tibiae slender and lacking teeth, tarsi 5-segmented but appearing 4-segmented, fourth segment deeply bilobed, claws toothed at the base.

Distribution

The wider distribution includes the whole of Europe north to the Arctic Circle in Scandinavia, northwest Africa, Iran, Israel, Ukraine etc. and east into western Siberia.

Habitat

On the continent it is locally common and appears on a wider range of fungi e.g. in Scandinavia mainly on Hypoxylon fragiforme, which occurs mainly on Fagus (beech) but also on other broadleaf trees, H. multiforme (mainly on birch) and H. fuscum (birches) as well as Daldinia concentrica, in northern areas mostly on Daldinia loculata which develops on fire-damaged birch and it has been recorded from other species e.g. Ustulina deusta (develops on a wide range of broadleaf trees) and Fomes fomentarius (mostly on birch in the north, more catholic in southern areas).