the longest span of any arthropod. They are typically found in the Pacific waters near Japan on the bottom of the continental shelf. The lion's mane jellyfish (Cnidaria: Cyanea capillata) is the largest known type of jellyfish. Their tentacles can reach up to 190 feet long, and they may have a bell diameter of almost 7 feet. These animals are usually found in cold northern Arctic waters and in the Northern portions of the Atlantic and Pacific Oceans. The giant squid (Mollusca: Architeuthis dux) comes from the family Architeuthidae. These squid are both the largest known cephalopod and the largest known mollusc. They can grow to a length of about 45–50 feet long. They developed large eyes, the largest of any animal, to be able to detect small amounts of bioluminescence in the dark and deep ocean where they live. References External links A Study Guide to Invertebrate Zoology ~ at Wikibooks Online Dictionary of Invertebrate Zoology Zoology Subfields of zoology