Cnidarian, or, Coelenterate, an animal of the phylum Cnidaria, or Coelenterata. The phylum includes the corals, hydras, jellyfish, Portuguese man-of-war, and sea anemones. Cnidarians are water-dwelling animals. The body is typically cylindrical or bell-shaped and has a single opening used for taking in food and excreting wastes. Arranged around the opening are tentacles armed with cnidocytes, cells used to sting prey and enemies. Some cnidarians live singly, others in large colonies.The cnidarian has tentacles armed with cnidocytes, cells used to sting prey and enemies.
Although no one can yet tell how old lobsters get, they show no apparent signs of aging. Learn why lobsters live so long and get so big, and what this means for other animals, including humans.
Hermit Crab is a land- or water-dwelling crustacean. Unlike true crabs, hermit crabs have soft, vulnerable abdomens.