Deep-Water Octopus / I MacDonald

A deep-water octopus. Mollusca, a phylum that encompasses leggy invertebrates like the squid and octopus, along with their less charismatic and more oozy brethren — slugs, snails, clams — comes in second only to crustaceans for sheer number of species inhabiting the Earth’s oceans. 8,860 feet (2700 meters), Alaminos Canyon, Gulf of Mexico — via Our Amazing Planet