Tenthredinidae (Nematinae (Croesus septentrionalis))

Tenthredinidae (Nematinae (Croesus septentrionalis))

Observation - Tenthredinidae (Nematinae (Croesus septentrionalis)) - UK and Ireland. Description: My second observation of this sawfly, and still can't find an ID. Also wondering what the hind tibia are adapted for..? Hold cursor on larvae image.

My second observation of this sawfly, and still can't find an ID. Also wondering what the hind tibia are adapted for..?
Hold cursor on larvae image.