Octopus is the largest genus of octopuses, comprising about 100 species.

These species are widespread throughout the world's oceans.

Many species formerly placed in the genus Octopus are now assigned to other genera within the family.

The octopus has 8 arms, averaging 20 cm (8 in) long for an adult.

[1][2] The species listed above with an asterisk (*) are questionable and need further study to determine if they are valid species or synonyms.