Birch sawfly

Description:

Mature insects grow between 1.5-2.5cm. Usually a black, or reddish-brown bodied insect, though very rarely yellow forms occur. Males may have a red banded abdomen. The wings in both sexes have a clearly defined fuscous apical band. The pale cream membrane in the centre of the first tergite contrasts strikingly with the dark sclerotised portion. The antennae are mostly black with orange-yellow bulbous tips.

Habitat:

These sawflies prefer areas where Birch trees can be found.

Notes:

I had never seen this species before and was quite impressed by its size. Spotted at "De Motketel" near Vaassen, Veluwe, Holland. Sadly its right wing was heavily damaged and it seemed to be in an inactive state. This I believe is also known as dormancy. "Dormancy is an inactive state associated with metabolic depression and arrested development that promotes the survival of insects during periods of harsh environmental conditions, including high or low temperatures or moisture conditions and reduced food quality or availability. Diapause may occur in any life stage (egg, larva, pupa, or adult); however, for a given species it generally occurs in only one stage. Dormancy may be manifested in a variety of forms that differ widely in their intensity and duration. Consequently, it has proved difficult to classify these forms into discrete categories, and general agreement on terminology is lacking. Nonetheless, dormant states range from a moderate depression of short duration (quiescence) to a profound and extended period of metabolic suppression and developmental arrest (diapause)." ~ https://what-when-how.com/insects/dorman.... (sources:see reference)