The southern blue-ringed octopus (Hapalochlaena maculosa) is one of three closely related species belonging to the genus Hapalochlaena. Despite its small size, it is considered to be one of the world’s deadliest venomous animals. The upper surface of the southern blue-ringed octopus has a rough texture and is covered in wrinkles. At rest, this species is well camouflaged, being grey to beige with light brown patches on the body and arms. However, when the octopus is disturbed or threatened, special pigment cells in the skin called ‘chromatophores’ become activated to display as many as 60 iridescent blue rings on the mantle and arms, which act as a warning signal. It is these blue rings which give the southern blue-ringed octopus its common name. The southern blue-ringed octopus is named for the small, iridescent blue spots it develops when alarmed. The toxin in the southern blue-ringed octopus’s venom is 1,000 times more powerful than cyanide. The female southern blue-ringed octopus carries its eggs until they hatch, and dies shortly afterwards.