I don’t really know what’s going on here. Acronicta afflicta, fifth instar. Video was taken through a dissecting scope by an undergrad in the lab while I was away last week. Turns out most of these were pretty sick (most are dead now, only one has made it to the 6th instar so far)… so perhaps this was an early stage of the illness? Or just a post-molt behavior as its body plumped up?

Either way, it’s a little silly.