Species Cryptorhynchus lapathi - Poplar-and-Willow Borer

Poplar-and-Willow Curculio, Mottled Willow Borer, Willow Beetle, Withy Weevil

Cryptorhynchus lapathi (Linnaeus)

Orig. Comb: Curculio lapathi Linnaeus, 1758

lapathus (L). 'sorrel'

5.6–8.3 mm(1)

Holarctic; in NA, northern transcontinental (south to NC-IL-SD-UT-OR) - Map (2); it is not clear if the species was introduced into NA from Europe or is a native Holarctic species(1)

Adults and larvae asso. w/ var. spp. of willow, poplar, alder and birch (Salicaceae, Betulaceae);

larvae mine young stems(1)

Adults appear in late July and August, feeding on the inner bark of young shoots. Eggs are laid singly or in groups of 2-4 in slits cut in the corky bark often in scar tissue. Young larvae feed in the cambial layer and outer layer of sapwood tunneling in all directions and pushing our their borings in small holes. When ready to pupate, the larvae bore upward and inward, constructing cells in the stem's center.(3)

One generation per year(3)

Overwinter as larvae(3)