What is this

I found this isopod in my year-old Porcellio Scaber colony. It's completely different from the other specimens: it can curl up into a ball, isn't as fast, and prefers to burrow in the substrate.

I tried to find something similar online, but couldn't find anything. Is this a morph or just a temporary coloration that will change as it grows?

u/Rerqsx — 11 days ago