Octopus cyanea
species of mollusc
Octopus cyanea, also known as the big blue octopus or day octopus, is an octopus in the family Octopodidae. It occurs in both the Pacific and Indian Oceans, from Hawaii to the eastern coast of Africa. O. cyanea grows to 16 cm in mantle length with arms to at least 80 cm. This octopus was described initially by the British zoologist John Edward Gray in 1849; the type specimen was collected off Australia and is at the Natural History Museum in London.
Description
Living as it does on coral reefs, and hunting by day, O. cyanea is adept at camouflage and not only can change colour frequently, but also can change the patterns on and texture of its skin. One researcher observed it change its appearance 1000 times in seven hours. As it moves across the seabed it makes changes in its colouring and appearance to match the substrate beneath. The colour changes are instantaneous and made by chromatophores under direct control of the brain. This octopus sometimes produces a "passing clouds" display when stationary near prey such as a crab; this mimics a dark shadow passing across its surface and may encourage the crab to move incautiously.
Distribution
O. cyanea is found on reefs and in shallow waters in the Indo-Pacific.
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This entry incorporates text from “Octopus cyanea” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.