Curculio glandium Marsham, 1802 ♀
Common names: Acorn weevil [En], Charançon du chêne, Balanin des glands [Fr], Eikelboorder [Nl], Eichelbohrer [De]
Meise, BRABANT ● Belgium
Description: This weevil has a length of 4-8 mm.
The most striking feature of the acorn weevil is its elongated snout, known as a 'rostrum', which is longer in females than males. Adults have a brownish and patterned body. The larvae are short, and cylindrical in shape, and move by means of ridges on the underside of the body.
Wevils in this genus can be hard to tell apart. C. nucum has broader segments of flagellum and the segments are covered with standing-off setea which in C. glandium are adjacent.
Biology: Adults feed on oak. The females lay their eggs in acorns; the long rostrum is used to bore through the thick wall of the nut with jaws located at the tip of the rostrum. When it has almost reached the centre of the nut, the egg is inserted in the hole, which subsequently heals up. The larvae develop inside the acorns, burrowing out when they are fully-grown in order to pupate in the soil, leaving a small hole in the wall of the acorn.
Habitat: This species is found on oak trees.
Distribution: Asia, mainly in southern and central parts of Europe, becoming increasingly rare further north.
Arkive, Curculio glandium
Harde, K. W., 2000. A field guide in colour to beetles. Silverdale Books, Leicester.
Joy, N. H., 1949 British beetles: their homes and habits. Frederick Warne & Co Ltd., London.