Greater blue-ringed octopus

Hapalochlaena lunulata · The greater blue-ringed octopus is a small, extremely venomous octopus that lives in the shallow tropical and subtropical waters of the Indo-West Pacific.

Greater blue-ringed octopus
Photo: Jens Petersen, CC BY 2.5
Greater blue-ringed octopus
Photo: Rickard Zerpe, CC BY 2.0
Greater blue-ringed octopus
Photo: Elias Levy, CC BY 2.0

Taxonomy

KingdomAnimalia
PhylumMollusca
ClassCephalopoda
OrderOctopoda
FamilyOctopodidae
GenusHapalochlaena
SpeciesHapalochlaena lunulata

Where it lives

Tide pools and reefs from Sri Lanka to Japan, the Philippines and Australia.

Fun facts

  • This octopus is small, no longer than 10 centimetres including its arms, yet it is one of the most toxic marine animals in the world.
  • Its skin has around 60 electric-blue rings, which act as a warning to predators that it is highly venomous.
  • When it flashes its glowing blue rings as a warning, each flash lasts only about a third of a second.
  • It hunts by pouncing on prey, grabbing it with its arms, and using its beak to pierce a crab's tough shell and release venom that paralyzes the prey.

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Facts and taxonomy adapted from Wikipedia (CC BY-SA 4.0).