- Blue-ring Octopus
- Lesser Blue-ringed Octopus
Small muscular, short-armed octopus. Repeated colour pattern of brilliant iridescent blue rings over the body, head, arms and webs. Body oval in shape often with an extended pointed tip at the rear. Capable of excellent camouflage, hiding the blue markings and pushing up small bumps and spikes on the head and mantle. Mantle length to 6 cm, total length to around 22 cm.
This small octopus forages mainly at night feeding largely on crustaceans, particularly crabs. As in all blue-ringed octopuses, this species has large salivary glands that produce very strong toxins. The toxins are used to quickly paralyse their prey but also act as a good defence against attackers. The brilliant blue displays warn potential predators to keep away. This species of blue-ringed octopus has lost the ability to produce ink. It is possible that the strong toxins are enough to protect this octopus. Other members of the group can still produce ink. Mating occurs by males approaching females and climbing on to their bodies. The male inserts his third right arm into the female's gill cavity and passes sperm packets into her oviducts. The female lays large eggs in strings and carries them with her in her webs. The large young hatch with full colour patterns and immediately settle to the seafloor.
Rocky reefs, rubble areas and seagrass meadows, from the intertidal to a depth of at least 50 m.
Direct threat to humans. Saliva contains the potentially lethal neurotoxin tetrodotoxin.
Native to Australia
- DSE Advisory List : Not listed
- EPBC Act 1999 : Not listed
- IUCN Red List : Not listed