The Colossal Squid, sometimes called the Antarctic or Giant Cranch Squid, is believed to be the largest squid species, and the only member of the genus Mesonychoteuthis. Current best estimates put its maximum size at 14 meters (46 feet), based on analysis of smaller and immature specimens, making it the largest known invertebrate. Unlike the various giant squid species whose tentacles are equipped with suckers lined with small teeth, the tentacles of the Colossal Squid are tipped with a fierce mixture of suckers and swiveling hooks. While little is known about the life of this creature, it is believed to hunt prey such as chaetognatha and squid in the deep ocean using bioluminescence. Based on capture depths of a few specimens, as well as beaks found in sperm whale stomachs, the adult squid ranges at least to a depth of 2200 m, while juveniles can go as deep as 1000 m.