Opisthoteuthis massyae is an octopus living in the eastern Atlantic Ocean.
O. massyae occupies the benthic zone (seafloor and water immediately above) of the open ocean.[2] The octopus lives from 600 m (2,000 ft) to 1,500 m (4,900 ft) deep.[1] It's found as far north as Ireland, in the Rockall Basin,[3] and as far south as Namibia.[4] There are more specimens in the southeast Atlantic than in the northeast Atlantic.[5]
The two foremost arms of mature males are thicker than their other six arms. This is unusual for Opisthoteuthis species. Mature males also have some enlarged suckers, which is more typical of the genus. Males have more suckers than females.[5] Specimens with longer arms generally have more suckers.[6] Males weigh more than females; males can reach a weight of 5,750 g (12.68 lb), and females a weight of 2,959 g (6.523 lb). Females may lay eggs throughout their lifetimes.[5]