I just recently got my first tortoise, he is a little Greek tortoise and I've been trying to monitor his health as well as I can and look for abnormalities. I briefly saw these spots before but thought it was a little bit of water until just now I realized it's just a small smooth protrusion on the shell. I've added a picture but you can't see it too well. Does anyone know what these are? Most of his shell has little bumps but it's completely smooth here.