Phyllobius oblongus (Linnaeus, 1758)
This very distinctive and rather atypical Phyllobius is the only member of the subgenus Nemoicus Dillwyn, 1828, a group that has occasionally been considered as a distinct genus. It is a native and locally common species throughout Europe including Corsica, Sardinia and the Canary Islands etc. extending north to Scandinavia and east to Siberia, and in the Nearctic it is adventive and established in the north-eastern United States and eastern Canada. It is generally common throughout England and Wales extending to West Perth in Scotland. Typical habitats are wooded borders, hedgerows and wooded parkland etc. and the adults are active from April until July although at higher latitudes the season may extend to the end of August. Adults are short-lived; they feed upon tender foliage for a week or two and then disperse by flight and so local populations may appear and disappear quite suddenly, they feed on the fresh foliage of a wide range of trees and shrubs e.g. Salix spp., Crataegus monogyna, Tilia cordata, T. vulgaris, Quercus spp., Ulmus procera and Ulmus glabra etc. and were formerly a pest of various orchard species including Pyrus, Malus, Prunus and Corylus, they are also known to feed on blossom and we have swept them from various umbel flowers. Despite this they are seldom seen in any numbers; they tend to be swept or beaten as single specimens or pairs. Following a period of feeding and dispersal they begin mating in late April and May, and females deposit eggs in the ground around the base of the host plants during June. Larvae live freely in the soil feeding upon the root surfaces and developing slowly; they are fully grown by the autumn and overwinter in the soil. Pupation occurs in an underground cell during early spring and the adults eclose shortly after. Like the adults the larvae are widely polyphagous, feeding upon the roots of a wide range of woody plants but perhaps Salix, Quercus, Ulmus and various fruit trees are favoured hosts in the U.K. Herbaceous plants are sometimes attacked e.g. in the United States and Canada it is a pest of cultivated strawberries.
Phyllobius oblongus 1
Phyllobius oblongus 2
Phyllobius oblongus 3
3.5-6.0mm. A bicoloured weevil; body entirely black with generally brown elytra which lack metallic scales, and the entire dorsal surface with sparse pale pubescence. The head is strongly punctured but for a shiny median longitudinal strip, and with strongly convex eyes in front of long temples which are gradually broadened to the base. Rostrum quadrate or slightly transverse; the scrobes straight to the anterior margin of the eyes and generally obscured by pubescence. Antennal scape long, curved and weakly broadened towards the apex, funiculus 7-segmented; segments 2 and 3 subequal, combined as long as 4-7, and 9-11 form a weak club. The pronotum is strongly and densely punctured, becoming confluent laterally; the lateral margins are curved, broadest near the middle and lack borders. Elytra sinuate behind prominent shoulders and broadest behind the middle, the striae are strongly punctured to the apex, and the interstices flat, shiny and each has a row of very fine punctures. The legs are pale and pubescent throughout, and all femora are toothed below. The male pro-tibiae have a strong hook on the inner apical angle; this is much less developed in the female. Claws connate. The basal abdominal sternites are depressed in the male and smooth in the female. Typical specimens are simply bicoloured but the elytra may be variously darkened, especially laterally, and entirely black specimens occur on the continent.