Octopus is the largest genus of octopuses, comprising more than 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 long for an adult. Species Octopus alatus Sasaki, 1920 (taxon inquirendum) Octopus alecto Berry, 1953 Octopus araneoides * Iw. Taki, 1964 (taxon inquirendum) Octopus arborescens Hoyle, 1904 (taxon inquirendum) Octopus argus Krauss, 1848 Octopus australis Hoyle, 1885 – hammer octopus Octopus balboai Voss, 1971 Octopus berenice Gray, 1849 Octopus berrima Stanks & Norman, 1992 – southern keeled octopus Octopus bimaculatus Verrill, 1883 – California two-spot octopus or Verrill's two-spot octopus Octopus bimaculoides Pickford & McConnaughey, 1949 – California two-spot octopus Octopus bocki Adam, 1941 – Bock's pygmy octopus Octopus briareus Robson, 1929 – Caribbean reef octopus Octopus bulbus Norman, 2001 Octopus californicus Berry, 1911 – North Pacific bigeye octopus Octopus campbelli Smith, 1902 Octopus chierchiae Jatta, 1889 – lesser Pacific striped octopus Octopus conispadiceus Sasaki, 1917 – chestnut octopus Octopus cyanea Gray, 1849 – big blue octopus or Cyane's octopus, Octopus diminutus Kaneko & Kubodera, 2008 Octopus djinda Amor, 2021 Octopus favonius Gray, 1849 Octopus filamentosus Blainville, 1826 (taxon inquirendum) Octopus filosus Howell, 1867 Octopus fitchi Berry, 1953 – Fitch's pygmy octopus Octopus fujitai Sasaki, 1929 (taxon inquirendum) Octopus gardineri Hoyle, 1905 Octopus globosus Appellöf, 1886 (taxon inquirendum) – globe octopus Octopus gorgonus Huffard, 2007 Octopus harpedon Norman, 2001 Octopus hattai Sasaki, 1929 Octopus hawaiiensis Eydoux & Souleyet, 1852 Octopus hongkongensis Hoyle, 1885 (taxon inquirendum) Octopus hubbsorum Berry, 1953 – Hubb's octopus Octopus humilis Huffard, 2007 Octopus hummelincki Adam, 1936 – bumblebee two-spot octopus or Caribbean two-spot octopus Octopus huttoni Benham, 1943 Octopus incella Kaneko & Kubodera, 2007 Octopus insularis Leite & Haimovici, 2008 Octopus jeraldi Pratt, Baldwin & Vecchione, 2020 Octopus joubini Robson, 1929 - Atlantic pygmy octopus or small-egg Caribbean pygmy octopus Octopus kaharoa O'Shea, 1999 Octopus kaurna Stranks, 1990 – southern sand octopus Octopus kermedecensis Berry, 1914 Octopus laqueus Kaneko & Kubodera, 2005 Octopus longispadiceus Sasaki, 1917 (taxon inquirendum) Octopus mariles Huffard, 2007 Octopus maya Voss & Solís, 1966 – Mexican four-eyed octopus Octopus mercatoris Adam, 1937 Octopus mernoo O'Shea, 1999 Octopus microphthalmus Goodrich, 1896 Octopus micropyrsus Berry, 1953 – California Lilliput octopus Octopus micros Norman, 2001 Octopus mimus Gould, 1852 Octopus minor Sasaki, 1920 (taxon inquirendum) O. m. minor Sasaki, 1920