Dumbo octopus refers to one of the 13, 14, 17 or 18 species – scientists haven’t agreed yet on how many species have been discovered – of deep-sea octopuses (that’s the generally accepted plural; not octopi) in the genus Grimpoteuthis. They are one of the cutest sea creatures but also one of the rarest, which is why not much is known about them. They remain mysteries of the deep. So far, here’s what we know: