Dogfish are technically sharks because they belong to the subdivision Selachii, which comprises all modern sharks. The smallest dogfish on the planet is the dwarf lanternshark (Etmopterus perryi). It only lives in the warm waters of the Caribbean, off the northern coast of Colombia and Venezuela, and it reaches just 16 or 17 centimetres (6.3-6.7 inches) long when fully grown. They look just like larger shark species, with the same elongated eyes, pointed nose and asymmetrical tail. They are called lanternsharks because they have light-emitting organs in their skin that produce vivid-coloured markings while the fish is alive. Some of these markings attract mates, but others replace the sunlight shining from above so that the lanternshark doesn’t present a dark silhouette to any predatory fish which might be below, acting like an ‘invisibility cloak’.