Octopus cyanea
Date 1886
Source Report on the Cephalopoda collected by H. M. S. Challenger during the years 1873-76 William Evans Hoyle, 1855-1926
Author A Pollock
Source: https://commons.wikimedia.org/wiki/File:Octopus_cyanea3.jpg

The big blue octopus or day octopus (Octopus cyanea) is an octopus in the family Octopodidae. Octopus cyanea is found on reefs and in shallow waters in the Indo-Pacific. Its range extends from the Red Sea, the East African coast, and Madagascar, to southeastern Asia, Oceania, and as far as Hawaii.