What Is the Smallest Octopus in the World
The smallest octopus in the world is the star-sucker pygmy octopus, also known as Octopus wolfi. Adults measure about 1.5 centimeters in total length, including arms, and weigh less than 1 gram. This species is recognized as the smallest known octopus by marine taxonomy databases and scientific collections.
Another very small species is the Atlantic pygmy octopus, Octopus joubini, which reaches roughly 3 to 5 centimeters in length. While larger than the star-sucker pygmy, it is still among the smallest cephalopods kept in home aquariums and studied in labs.
Where the Smallest Octopus Lives
The star-sucker pygmy octopus is found in shallow tropical waters of the western Pacific Ocean, particularly around Indonesia, the Philippines, and Papua New Guinea. It lives on rubble and sandy bottoms near coral reefs, often at depths between 10 and 50 meters.
Researchers document these tiny octopuses in coastal reef systems where they hide among shells, coral fragments, and small crevices. Their small size and camouflage help them avoid predators, and they are typically nocturnal hunters of tiny crustaceans and worms.
Why the Smallest Octopus Matters for Science
Studying the smallest octopus in the world helps scientists understand cephalopod miniaturization, brain structure, and behavior. Researchers use species like Octopus wolfi to compare neural circuits and hunting strategies across octopus sizes.
Public aquariums and research institutions share observations on the care and biology of tiny octopus species. These efforts support conservation awareness and improve husbandry practices for delicate small cephalopods in controlled environments.