The animal is in the class Cephalopoda which is composed of the squid, octopus and nautilus. Most are predatory carnivores.
Only the female secretes the shell, the male Argonaut is much smaller and does not have a shell. They are usually found in tropic or temperate seas. The female can grow to the length of 2 feet and produce a shell as big as 14 inches long, these are nowhere near that size. They swim near the surface of the water and prey upon pteropod mollusks and small pelagic fish. Sailfish in turn, prey upon them.