Algae octopus

Abdopus aculeatus

Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Order: Octopoda
Family: Octopodidae
Genus: Abdopus
Species: Abdopus aculeatus

The algae octopus (Abdopus aculeatus) is a small, shaggy-looking octopus that disguises itself as a clump of seaweed and can even 'walk' on two arms across the bottom. Raised skin papillae and mottled green-brown colours let it vanish among algae and seagrass.

Its mantle is only a few centimetres long, with arms reaching around 10-15 cm. Unusually, it is active by day, hunting crabs and other crustaceans in shallow intertidal pools and reef flats, and it is known to leave the water briefly to cross between tide pools. It was one of the first octopuses filmed using bipedal walking as camouflage.

Algae octopuses live in the shallow waters of the western Pacific, including the Philippines, where they are found on seagrass beds, rubble and reef flats. Divers and snorkellers may spot them in very shallow water, if they can tell octopus from weed.