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Pachyrhinus lethierryi (Desbrochers, 1875)

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POLYPHAGA Emery, 1886

CURCULIONOIDEA Latreille, 1802

CURCULIONIDAE Latreille, 1802

ENTIMINAE Schönherr, 1823

POLYDRUSINI Schönherr, 1823

Pachyrhinus Schönherr, 1823

Native to the Mediterranean region the natural range of this species included the south of France, Corsica, Sardinia and Sicily, but since the 1980s it has spread rapidly into many European countries and has recently been recorded from Asia Minor and the Crimean Peninsula to the east and Germany, the Netherlands and the UK to the north, it has long been known to occur among translocated nursery stock and this is thought to be the principal method of dispersal. It was first recorded in the UK in 2003 from Hertfordshire and since that time has spread rapidly through England to South Yorkshire and there are records from Wales and further north to southwest Scotland. Host plants include various conifers widely used for domestic hedges, commonly Leyland Cypress (Cupressus x leylandii A. B. Jacks. & Dallim.), Lawson Cypress (Chamaecyparis lawsoniana (A. Murray bis) and Thuja occidentalis L., including their various cultivars, and sometimes on other cultivated conifers such Junipers (Juniperus L.). Typical habitats are hedges and ornamental trees in parks and gardens and, despite the adults being strong fliers, they are rarely found away from cultivated trees. Breeding occurs in spring and early summer and larvae develop in the soil among the host roots, they overwinter in the soil and complete their development in the spring. Pupation occurs in a cell constructed among the roots and adults emerge during May and June, they persist into August but generally die-off after mating and ovipositing. Adults are easily sampled by sweeping host foliage; they generally occur in numbers and have been recorded on walls and windows in sheds and houses.

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3.5-4.5 mm. Elongate and rather parallel-sided, body black with dense green scales above and below, occasionally with whitish scales to the head, and variety lostiae Desbrochers has pink scales to the ventral surface, legs extensively pale but usually with the femora and tibiae to some extent darkened, antennae darkened apically, Head evenly convex above and forming a continuous curve in side view, with convex and prominent eyes and long diverging temples, rostrum transverse with a transverse glabrous ridge between the antennal insertions, scrobes lateral and curved down to the ventral margin of the eyes. Antennae long and slender, scape curved and only weakly widened from the base, all funicular segments elongate and the club long and slender. Pronotum transverse; broadest behind the middle and narrowed to a straight basal margin and a slight constriction before the curved apical margin. Elytra elongate with rounded shoulders  and slightly dilated behind the middle, in side view flat in the basal third and convex before a steep declivity, surface with dense recumbent  elliptical scales and fine semi-erect pubescence which is clearly visible around the apical margin, with narrow and punctured striae complete to the apex and broad, flat interstices. Legs long and robust, front femur strongly toothed, hind femora with a small but obvious ventral tooth. Claws fused at the base.

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