Cephalopods are among the mollusks, such as snails and clams. Therefore, you will not find this section under the fish, but under molluscs
At present, about 800 species are known from today's seas, and new species are constantly being described.
They are not in high demand in normal home aquariums, which is good.
Nevertheless, certain species are often seen in larger zoos.
Keeping octopus species is not that easy.
They like to break out, they play a lot and are very, very smart, not to say intelligent.
Without rank: Protostomia
* Superorder Belemnoidea (thunderbolt)
* Superorder Decabrachia (ten-armed squid)
o order Sepiida (cuttlefish)
o order Spirulida
o order Sepiolida (bobtail squid)
o order Teuthida (squid)
* Superorder Vampyropoda (eigtharm cuttlefish)
o order Vampyromorpha (vampire squid)
o ok Octopoda (octopus)
o order Cirroctopoda (cirrus octopus)