1. Body shape and appearance: The blue striped octopus is a small octopus with a body length of about 20 cm and an average weight of 38 grams. The upper body surface is rough and wrinkled, usually gray, beige, dark brown, dark yellow to brown. When in danger, special pigment cells in the skin are activated, and as many as 60 rainbow-colored blue rings and spots will be displayed on the body surface and wrist. These blue-green fluorescent dots and blue rings are their warning colors. In contrast, the blue-ringed octopus is smaller, its arm span is less than 15 cm, its body surface is yellowish brown, and its characteristics are not obvious.
2. Venom: The salivary glands and ovaries of the blue octopus contain tetrodotoxin and amines, which are extremely poisonous. Once they feel threatened, they are bitten directly, and their venom is enough to kill a person. However, the blue-ringed octopus is also extremely toxic, and the poison of one blue-ringed octopus can kill more than 20 people.
3. Habitat and food: The blue striped octopus mainly lives in small caves on shallow reefs along the coast and feeds on crabs and other arthropods. The blue-ringed octopus is mainly distributed in the Pacific Ocean, especially between Japan and Australia.