Diprion pini

Common pine sawfly
Female
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Suborder:	Symphyta
Superfamily:	Tenthredinoidea
Family:	Diprionidae
Genus:	Diprion
Species:	N. pini
Binomial name
Diprion pini (Linnaeus) 1758

Diprion pini, the common pine sawfly, is a sawfly species in the genus Diprion. It is a serious pest of economic forestry, capable of defoliating large areas of pine forest. Since it feeds until late in the autumn, affected trees are weakened and often die in the subsequent winter. The species is found all across Europe, with outliers elsewhere. It affects the Scots, mountain, eastern white, radiata, lodgepole and black pines. Scots pines are not generally killed by a single defoliation, but weakened trees may suffer increased attack by bark beetles, buprestid beetles, and pine weevils, which can kill trees, as can repeated defoliation.

Mass of larvae on pine tree

Larval damage to pine

Last instar larva with exuviae

Larva forming cocoon in pine tree

Opened cocoon

Male imago

Female imago

Deimatic behaviour: group of larvae waving their heads simultaneously

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Wikipedia