Common name: Greater blue-ringed octopus

General information

The Blue-ringed Octopus, specifically the Greater Blue-ringed Octopus (Hapalochlaena lunulata), is a highly venomous marine animal known for its striking blue rings that appear vividly when it feels threatened. Despite its small size, typically 12 to 20 cm (5 to 8 inches) including arms, it possesses a potent neurotoxin called tetrodotoxin, which it uses for defense and to capture prey.

Due to its venomous nature, it is not recommended for the average aquarist. However, it is sometimes kept by highly experienced hobbyists in species-specific tanks with secure lids to prevent escape.

Care

The Blue-ringed Octopus requires a specialized aquarium setup that mimics its natural habitat. A well-established tank with plenty of hiding spots and a secure lid is crucial. They are escape artists and can fit through incredibly small gaps. The tank should also have a stable water quality, with regular monitoring and maintenance.

Feeding can be challenging as they prefer live food, such as small crabs and shrimp. It's important to handle feeding with care due to the risk of envenomation.

Reproduction

Reproduction in captivity is rare and not well-documented. In the wild, after mating, the female lays eggs and tends to them until they hatch, after which she typically dies. The care of the offspring in a captive environment would be extremely challenging due to their specific dietary and environmental needs.

Habitat

Hapalochlaena lunulata is found in tide pools and coral reefs across the Pacific and Indian Oceans, from Japan to Australia. They prefer shallow waters where they can find ample shelter and food sources.