Phloeophagus lignarius (Marsham, 1802)

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POLYPHAGA Emery, 1886

CURCULIONOIDEA Latreille, 1802

CURCULIONIDAE Latreille, 1802

COSSONINAE Schönherr, 1825

RHYNCOLINI Gistel, 1848

Phloeophagus Schönherr, 1838

This widely distributed though very local and generally scarce species occurs throughout Europe and western Russia, to the north it extends into the southern most parts of Fennoscandia where it is now very rare e.g. it is absent from Finland, there are only a very few records from the southern coast of Norway and a few from southern Sweden (where it is red-listed), and the UK where it is local across southern and central England, although generally absent from the West Country, and sporadic and rare in Wales and further north to the Scottish Highlands. Adults are associated with a wide range of deciduous trees including horse chestnut, beech, hawthorn, ash, hornbeam, elm, oak, poplar and willow and in Europe occasionally on various conifers. Typical habitats are damp deciduous woodland and old established parkland, wooded river valleys and verges etc., especially where there is a good supply of standing timber in various stages of decay, adults are nocturnal and difficult to find as they tend to remain among loose or damaged bark but they may be found wandering the surface on warm summer nights, they often appear in damp rot-holes and have been beaten from ivy growing on dead trunks. Mating occurs in the spring and larvae bore into hard, dead heartwood, often in cavities or below branch junctions or in old ammoniacal wood below bird nests, they are thought to complete their development during the summer and into the autumn as pupae have been found in November. Infestations tend to be long-lived and large old stumps may host them for decades, adults inhabit the substrate for much of the year and so taking extraction samples can be a good way of finding them at any time but all our records of adults are from specimens taken from the surface of old dead oak and beech at night in our local park between April and July.

Phloeophagus lignarius 1

Phloeophagus lignarius 1

2.8-3.6mm. Elongate and rather flattened, with a broadly rounded pronotum and near parallel-sided elytra, glabrous and entirely dark brown but usually with slightly lighter appendages. Head smoothly convex and finely punctured, with weakly convex eyes which are obvious from above and diverging temples, rostrum broad (although less than half the pronotal width) and parallel-sided, antennae inserted about half way along. Antennae distinctive; robust with a short scape that widens towards the apex, a 7-segmented funiculus composed of short transverse segments and a narrow, bluntly-pointed and pubescent club. Pronotum very slightly elongate, lateral margins smoothly curved from obtuse posterior angles to a strong sub-apical constriction, surface quite strongly punctured, closely so laterally but less so medially. Scutellum small but plainly visible. Elytral at most as wide as the pronotum, often slightly narrower, with rounded shoulders and straight lateral margins that are rather abruptly narrowed in the apical quarter to a continuously-rounded apical margin, surface with very strongly punctured striae complete to the apex and narrow, weakly convex and finely punctured interstices. Legs short and robust, the femora without ventral teeth and the external margin of all tibiae produced into an inwardly curved tooth at the apex. Tarsi pseudotetramerous with the third segment bilobed and broader then the second, claws smooth and lacking a basal tooth.

Along with the general appearance the combination of 7-segmented funiculus, parallel-sided rostrum, visible scutellum, and bilobed third tarsomere will distinguish Phloeophagus from similar members of the subfamily.