Nightgrazer

With the rise of Twilight Mosshrooms also came a creature which fed on them specifically. The Nightgrazer split off from the Crystalgrazer and moved into deeper waters where mosshrooms covering dead organisms were abundant. It eats the mosshrooms by cracking through their shells using its four-part beak to access the tasty insides. It has access to the midnight zone, and therefore the Crystal Mosshroom as well; it makes no difference to it what kind of mosshroom it eats. Its arms have changed slightly, with its lateral arms being a bit more leg like and its raptorial arm being straight and skinny—a bit like a terran batfish, but as a tripod—which is a slightly more useful setup for its benthic wanderings.

The Nightgrazer is otherwise like its ancestor. Its gut is filled with melter detritis which digest what it eats, and it in turn digests the melter detritis, much like a real-world ruminant. It has a circulatory system which pumps oxygen and nutrients directly dissolved in water through its body, lacking any blood pigment. It mates by linking its anal arm with another individual using its anal fingers, and it lays eggs, with shells made of sheets of living cells, which hatch into radially symmetric larvae.