Carries shells and debris for shelter, and is among the most reliably found animals on open silt.
Mantle to about 10 cm, total length to around 30 cm. The identifying combination is a dark brown to purple stripe running along the top of at least the first three arm pairs, dark angular veining across the arm crown, contrasting pink to white suckers, and dense papillae on the mantle running together into longitudinal bars. There is usually a pale cream wedge below each eye and a darkened margin to the arms and web — hence the alternative name veined octopus. The species it is confused with is the mototi octopus, and the separator is clean: the mototi carries a conspicuous blue-ringed false eyespot at the base of the web between the second and third arms, and this animal has none.
Forages at dusk and dawn, probing its arm tips into holes in the mud for shrimp and small fish, and buries itself in sediment. Its reputation rests on a specific and carefully argued piece of work: animals off North Sulawesi and Bali were recorded carrying cleaned bivalve or coconut half-shells across open sediment, stilt-walking awkwardly over the top of them, and assembling them into a shelter later. That qualifies as tool use precisely because the shell confers no benefit while it is being carried — it is cumbersome and it slows the animal down — and is transported for deferred use. It is worth stating that carefully, because “octopus lives in a coconut” is not tool use and misses the entire point. Bottles, clam shells and other discarded objects are used the same way. Recorded from the shallows to around 190 m on coastal mud and sand.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.
