Nedyus quadrimaculatus (Linnaeus, 1758)

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POLYPHAGA Emery, 1886

CURCULIONOIDEA Latreille, 1802

CURCULIONIDAE Latreille, 1802

CEUTORHYNCHINAE Gistel, 1848

CEUTORHYNCHINI Gistel, 1848

Nedyus Schönherr, 1825

Only three species of Nedyus have been described: Nedyus quadrimaculatus (Linnaeus, 1758) from the Palaearctic, N. flavicaudis (Boheman, 1844) from south eastern Canada and N vitiosis (Dietz, 1896) from the central United States. N. quadrimaculatus is a widespread European species recorded from Austria, Belarus, Bulgaria, Hungary, Italy, Moldavia, Norway, Finland, Denmark, Estonia, Germany, France, Greece, Latvia, Sweden and Switzerland. In the U.K. it occurs throughout England and Wales including the Isle of Wight, Anglesey and Man although in the West Country records are sparse. There are records scattered across Scotland to Shetland and the Western Isles. It is widespread but local in Ireland. Nedyus is generally very common and is one of our most frequently recorded weevils. Virtually restricted to nettles (Urtica dioica L.), the adults are active on emergent growth from the first warm days in early spring and are likely to be found wherever the host is growing. Their presence is soon obvious by the small, elongate holes made in young leaves as the adults feed. They are frequently found mating during the spring and eggs are produced from early spring to June or July. Larvae feed among the roots and rhizomes, producing a new generation of adults in late summer and autumn which will overwinter. Some die the following spring after breeding but a proportion enter diapauses and pass a second winter along with the new generation adults. Sweeping nettles will usually produce the adults in abundance during the spring, later than this they occur in small numbers into the autumn until the first cold spells. They may easily be overlooked in the sweep net as they often remain motionless for a while with the rostrum and legs withdrawn.

2.2-3.5mm Very convex, overall form broadly oval. Body black, with shiny cuticle. Head coarsely and densely punctured, variously clothed with pale elongate or oval scales which tend to be sparse in older specimens. Eyes convex, temples widened to base. Rostrum long, curved and punctured throughout. Female rostrum longer with the prorostrum longer than the antennal scape, in the male it is about the same length.  Antennae typically red

with a darker club but this varies. Scape short and gradually widened towards apex. Funiculus 7-segmented. Club broad and pointed. Pronotum strongly and densely punctured.  Front margin smooth and slightly raised, the area behind deeply impressed. Disc convex and with a pointed tubercle either side. Posterior margin strongly bordered, the area in front of this impressed. With dense pale scales laterally (side view), density of scales on disc variable. Scutellum not visible. Elytra quadrate, widest behind the shoulders, with the basal margin raised. Striae deeply impressed and a little narrower than the interstices.  Interstices flat, or virtually so, coarsely punctured and variously scaled; typically with a patch of pale scales across the middle of interstices 6 and 7, and another across the apices of the inner ones but specimens lacking this pattern occur. Without tubercles or with only a few weakly developed ones towards the apex. Legs dark or with the tibiae and tarsi lighter. Middle and hind femora toothed, front femur without, or with only a small tooth. Tarsi with two claws. Rostral channel long; extending to the posterior margin of the mid coxae. Male with mid and hind tarsi toothed at apex, first and fifth sternite shallowly impressed. Female without spurs or impressions.

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