The blue-ringed octopus is a marine animal.
 There are four confirmed species of Hapalochlaena, and six possible but still undescribed species being researched:Greater blue-ringed octopus (Hapalochlaena lunulata)Southern blue-ringed octopus or lesser blue-ringed octopus (Hapalochlaena maculosa)Blue-lined octopus (Hapalochlaena fasciata)Hapalochlaena nierstraszi was documented and described in 1938 from a single specimen found in the Bay of Bengal, with a second specimen caught and described in 2013
A benthic (bottom-dwelling) octopus typically moves among the rocks and feels through the crevices

