This octopus is typically grey to mottled brown with orange-rust red arm faces that taper to the tip. The eyes are usually white, and its skin consists of many small pavement-like patches and large papillae which can be raised over the body to produce a spiked appearance, common when imitating seaweed.

Shallow rocky reefs, not usually found over soft sediments. This species can be seen hunting in shallow rock pools during the day. Not found in southern NZ, it is mainly found in the north of the North Island and in Australia.

A predator feeding on crustaceans such as crabs.

Recently scientists have found this species in large aggregations or "cities" this is unusual as Octopus are usually solitary. It's thought a lack of den sites may have lead to this phenomenon.

http://www.sciencemag.org/news/2017/09/scientists-discover-underwater-city-full-gloomy-octopuses
Photo Credit: Rod Morris. Photos available from www.rodmorris.co.nz