Today I took this video in Southern Bavaria, Germany.
Video: https://www.youtube.com/watch?v=cCy1eLM6aE0
A female Maculinea rebeli was continuously tapping the leaves of Picea abies with its antennae and forelegs. Anyone familiar with this phenomenon? Why did she do that? While I was there she returned several times to the same tree, but to different branches.