Octopus Cyanea Gray, 1849 (Mollusca: Cephalopoda) in Australian Waters: Description, Distribution and Taxonomy

Octopus cyanea Gray, 1849 is widely distributed throughout tropical waters of the Indian and Pacific Oceans, O. cyanea was originally described from an unspecified locality in Australian waters as "Coast of New Holland." This paper provides detailed description and diagnostic characters for this species based on Australian specimens, original data on Australian and wider distributions, and an updated synonymy. The extant syntype "a" (BMNH 1928.2.4.1) is designated as lectotype. O. cyanea occurs in association with coral reefs in northern Australian tropical waters from the southern end of the Great Barrier Reef, north to Torres Strait and west to North West Cape, Western Australia. The misuse of the name Octopus cyanea (and cyaneus) for a species from temperate Australian waters is also resolved.