The filter urchip split from the shelled urchip. It has changed its diet from crystal shrubite to filter-feeding. Its shell has become more dome shaped to keep it from being pulled off surfaces. Its hollow tooth now sucks in water and filters out the plankton. The front tentacle leg has become smaller and no longer grasps on like the other 3 so the longer hollow tooth can poke out. The poison spines on the back have nearly disappeared and have become 3 bumps. It has also become smaller so it will be harder to see. They can grasp on to most anything and have been known to hitch rides on swimming creatures now and then to get to different locations where the plankton is richer.
Living Relatives (click to show/hide)
These are randomly selected, and organized from lowest to highest shared taxon. (This may correspond to similarity more than actual relation)
