Species group: Octopus and Squid
Other common names: Lesser Blue-ringed Octopus, Southern Blue-ringed Octopus
Scientific name: Hapalochanis maculosa
Although a fascinating creature, the Blue-ringed Octopus produces venom for which there is no antidote, and human fatalities have occurred. Sadly, it is coveted by some due to its small size, color, and the “danger factor”, and is sometimes sold to novices who are unaware of its deadly potential (the telltale blue rings are not visible unless the animal is stressed). It should never be kept as a “pet” (obviously!).
The Blue-ringed Octopus is found along Australia’s southern coastline, most often around rocky tide pools, coral reefs and seagrass beds.
Appearance / health:
This small Octopus tops out at a mantle size of 5 cm (2 in) and leg length of 20 cm (8 in), and is colored brown to yellow with brown patches. The characteristic blue rings do not appear unless the animal is agitated, complicating species identification.
Public aquariums have had some success with this species, but like all it is short-lived and extremely sensitive to copper, ammonia, and nitrates in the water. It cannot release ink when threatened, relying instead upon its highly-toxic venom.
Behavior / temperament:
The Blue-ringed Octopus’ behavior is similar to that of other Octopuses, but it is diurnal. It evinces the same degree of intelligence, and remains within coral rubble or rock crevices when not hunting.
Considered to be among the most deadly of all venomous creatures, Blue-ringed Octopus should never be kept in private collections. There is no antivenin for the toxins it produces.
The natural diet is comprised largely of crabs, shrimp and other marine invertebrates.
Captive breeding has not been documented, and is not likely as the larvae are planktonic. Females guard their eggs for the 45-60 day incubation period, and usually expire shortly after they hatch.
Written by Frank Indiviglio