Phyllobius argentatus (Linnaeus,1758)
Quoted by Joy as common, there are mainland records for this species throughout England and Wales, records are most abundant from western Wales and more especially along coastal regions, a pattern not particularly reflected in England. Our only offshore records are from Anglesey and Skye. Scottish records are abundant north of Aberdeen with many centred around Glen More, otherwise there only a few from Dumfries and Galloway (NBN). This essentially arboreal species occurs throughout our Watford area on a variety of broadleaved trees. Early in their season the diurnally active adults are probably easiest recorded from Crataegus, a little later they are common on Quercus (Oak) and Betula (Birch) but also occur on Fagus (Beech) and Corylus (Hazel). They are also recorded from Populus, Salix and Alnus (Morris). During late May 2008 they were common on a Crataegus hedge shaded by Oak in Cassiobury park. Sweeping or beating low canopy foliage in parkland or on the edges of woods from late April through to early July (later in the north) is likely to produce adults. They generally occur either singly or in small numbers and usually among larger numbers of other Phyllobius species, especially P.pyri but also P.maculicornis and the usually herbaceous dwelling but highly adventitious P.viridiaeris and P.roboretanus.

A slender and elongate species, parallel sided and brilliant metallic green.

3.8-6.0mm. Upper surface with scales almost round to slightly elongate and with pale pubescence. Head elongate with large and prominent eyes, temples parallel, only a little wider than rostrum, upper surface wekly convex, pubescence almost recumbent. Rostrum quadrate, strobes appear transverse behind antennal insertions otherwise filled with scales so indistinct. Antennae long and narrow, a little longer than elytra, testaceous. Scape much longer than width of head, curved at base and evenly thickened to apex. Second segment of funiculus longer than first, segment four twice as long as broad, club narrow and pointed. Pronotum transverse, convex with sides evenly rounded at middle, constricted towards base and apex, surface coarsely and densely punctate, usually invisible beneath dense scaling, pubescence curved and slightly erect. Scutellum distinct, densely scaled. Elytra elongate (2:1) and convex, surface uneven; raised at humerous and behind scutellum, transversely depressed behind these raised areas then evenly convex to apex. Scales usually dense so that striae are barely visible, scales recumbent, pubescence semi-erect and long, as long as width of interstices on disc. Legs testaceous, as antennae. All femora strongly toothed and with metallic scales. Tibiae sometimes darkened towards apex.

Description from two Watford specimens at X20