|Euophryum confine (Broun, 1881)|
|This woodboring species, indigenous to New Zealand, was first recorded in Britain near London
in 1937 and in the following decade or so further specimens appeared through the home counties. The beetle may well have
been established long before this as it closely resembles another wood borer, Pentarthrum huttoni Woll.,
with which it may have been mistaken e.g. Allen 1942, 1944. Neither Fowler nor Joy mention the species. The first
domestic infestations were recorded in 1947 from Battersea and Willesden (Britton, 1961) and since that time infestations
have been found over a wide area. The species now occurs throughout the UK, including Shetland (Morris), among both
processed and structural timber and in the wild from a range of deciduous trees.
Hickin (1975) regarded the species as 'extremely common' in London. In domestic situations they attack damp and decaying
wood, often when this infested with the fungus Coniphora puteana (Morris), although they will also continue to attack
dried out timber previously attacked by rot. They will also feed on other materials infested with fungus e.g. cardboard and
paper (Hum, Glaser and Edwards, 1980). In the wild they occur in a wide range of dead and decaying timber; standing and
fallen wood in all stages of decay as well as discarded processed timber, we have found large numbers between the wet
delaminating layers of plywood in a Watford domestic garden. They are very common throughout our area, the adults appearing in
colonies beneath loose or damaged bark from April or May and remaining common in this habitat until the autumn. Specimens are
occasionally found during the winter. During the summer of 2007 they were abundant under and around damaged Horse Chestnut
bark across Cassiobury park and during June and July 2008 were numerous throughout Whippendell wood. They also occur among
samples of swept broad-leaved foliage during hot weather. The life cycle appears to be annual with adults emerging
simultaneously in large numbers. Adults are able to bore into damp wood and appear to be long lived (Britton, 1961).
This very distinctive beetle will soon become familiar in the field but two species are very similar: Pentarthrum huttoni Woll. and Euophryum rufum, specimens need to be examined carefully to distinguish the species.
2.5-3.6mm. Elongate, parallel and very convex, entirely dark brown or with legs and humeral spot lighter. Upper surface with very fine and sparse pubescence. Head behind eyes smooth and very finely punctate, rest of head coarsely punctate, eyes very small and protruding. Rostrum pointed forward, not received into a ventral groove, coarsely punctate becoming finer towards apex, widened from before antennal insertions. Antennae inserted about halfway, scrobes not visible from above. Scape short and clavate, widened from about halfway, funiculus 5 segmented, club 3 segmented and pointed. Pronotum wider than elytra, evenly rounded and widest behind middle, without borders. Strongly constricted behind front margin and coarsely and evenly punctured. Base of scutellum level with base of elytra which is straight, appearing truncate. Elytra with rows of strong punctures, interstices convex, finely and sparsely punctate. Ninth interstice strongly raised around apex so that elytra appear explanate from above, this is absent in Pentarthrum. Outer edge of tibiae produced to an evenly rounded, inwardly pointed long tooth, inner edge with a much smaller apical tooth. Last segment of all tarsi elongate with two claws. Male rostrum shorter; L:W about 2, about 2.7 in female.
The widespread but much less frequent E.rufum is very similar, here the rostrum is much more abruptly excised at base and the antennal club is rounded.
Allen, A.A. 1942. Pentarthrum huttoni in south east Herts. Ent.Mon.Mag 78:117
Allen, A.A. 1944. A new British species of Cossonini recorded in error as Pentarthrum huttoni. Ent.Mon.Mag 80:120
Britton, E.B. 1961. Domestic wood boring beetles. BM(NH)economic series 11A:27-28
Hum,M., Glaser, A.E., and Edwards, R. 1980. Wood boring weevils of economic importance in Britain. Journal of the institute of wood science 22:201-207
Damaged Horse Chestnut bark infested with Euophryum