Octopus macropus is primarily found in the Mediterranean and Caribbean Seas, as well as the tropical western and eastern Atlantic Ocean. O. macropus is characterized by long arms, with the first pair being longer than the others, and a shallow web. It is red in color with large white spots over its entire body and paired white spots down the arms. The body measures up to 15cm and the arms to more than a meter. O. macropus is exclusively nocturnal and has a narrow range of prey species. Most of the research done on this species is concerned with larval development and activity patterns.