Tried to take some photos of different individuals that day, but they all got blurred, so that details may hardly be seen.
Better imgs. made with good equipment by a friend may be shown later when i get them.
I stated, that this species was named after its "collar" - 1. (+2) white segment behind head, thus "collaris" at my flickr-photo.
This may be true, but the species-name may as well mean: belonging to / living at hills ?
Will try to clear that, for the moment i don't know the right translation.