Gypsonoma dealbana (Fröhlich,1828)
common cloaked shoot
polyphagous
Salix triandra, Hoek van Holland, 14.ix.2018 © Jan Scheffers
Populus x canadensis, ter Heijde, 19.x.2018 © Jan Scheffers
parasite
In the autumn the larva causes window feeding, while living is a quickly widening, frass-covered, silken tube that is attached to the underside of a leaf. Hibernation in a silken tube on a shoot. In the spring the larva bores into buds or catkins.
hostplants
Betulaceae, Salicaceae, etc.
Corylus; Crataegus; Populus alba, x canadensis, nigra; Quercus; Salix purpurea, triandra.
distribution within Europe
larva
Hancock & Bland describe the larva as follows: “Head yellowish brown to black. Body yellowish or pale pinkish white; pinacula greyish brown; prothoracic plate yellowish brown with darker margins or black; thoracic legs and anal plate dark brown.” At no essential point there is a difference here with the larva of G. oppressana. Contrariwise, Lepiforum (2018) presents pictures of oppressana larvae with a dark grey body; it should be noted however that these larvae have already hibernated and were feeding on buds.
notes
larvae of this polyphagous species were regularly found by Kopelke in the galls of Euura vesicator and viminalis. Generally this had resulted in the death of the sawfly larva.
references
Bradley, Tremewan & Smith (1979a), Buhr (1964b, 1965a), Hancock & Bland (2015b), Kopelke (1985a), Tomasi (2014a).