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Related to blue-ringed octopus: stonefish, Cone snail
Any of at least 10 species of octopus of the genus Hapalochaena, having bright blue spots and found in the Pacific Ocean, esp. near Australia. It poisons its prey with tetrodotoxin. See: tetrodotoxin
a mollusc in the order Octopoda which has eight legs and eats crustaceans and shellfish.