Opisthoteuthis chathamensis, commonly known as the roughy umbrella octopus,[1] is a species of cirrate octopus restricted to demersal habitats surrounding the Chatham Rise in New Zealand. It is commonly known as the roughy umbrella octopus.[2]
Specimens have been recorded solely on soft sediments from 900–1438 meters deep.[3] [4] The type locality of O. chathamensis is near the Chatham Islands at 44°44'S, 77°15'W, 1180 m. The species is known only from this area of the Chatham Rise and off the eastern coast of the North Island of New Zealand.[5] O. chathamensis reaches a maximum length of 18 cm TL, and a mantle length of 5.4 cm. They are described as having subequal arms with around 41-45 suckers in males and 45-55 suckers in females.[5] Their oral surface and the webbing between their tentacles is maroon and the suckers are a pale cream.[6] O. chathamensis is listed as Critically Endangered by the IUCN due to a 70% decrease in population size in recent years, and has not been seen since 1999, when it was a common bycatch species. In addition, their longevity, low fecundity and slow growth (especially embryonic development which lasts 1.4-2.6 years among other species in the genus) has made them particularly susceptible to population declines and slow recoveries.