Opisthoteuthis pluto | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Order: | Octopoda |
Family: | Opisthoteuthidae |
Genus: | Opisthoteuthis |
Species: | O. pluto |
Binomial name | |
Opisthoteuthis pluto | |
Opisthoteuthis pluto is a deep-sea cirrate octopus found off southern Australia in the bathyal zone. [3] The species was described by S. Stillman Berry in 1918 [4] , and has recently been re-described [5] . The species is named for the Greek and Roman god of the Underworld. [6]
The octopus is known from multiple specimens. The largest specimen, a male, spanned 540 mm (21 in) from arm tip to arm tip [4] . Like other members of the genus Opisthoteuthis , this octopus is sexually dimorphic, the males having enlarged suckers on distinct regions of the arms [3] . The species has 80–85 suckers per arm, with males having a region of proximal suckers enlarged (from the 4th to 9th or 10th sucker, near the mouth). The species is distinct in lacking any distally enlarged suckers on the male [5] . Some sources note the species as having enlarged suckers on distal arm regions [4] , but this was not noted in Berry's original description and seems to stem from confusion with the recently described Insigniteuthis obscura [5] . The species has 8 lamellae on each gill, and unlike other southern Australian Opisthoteuthis has a unilobed digestive gland (liver), it has some unique modifications to its reproductive system that distinguishes it from other species [5] . According to S. Stillman Berry, who described O. pluto, the octopus was capable of partially retracting its suckers and cirri (the small tendrils lining the arms). [4] The octopus has a dark color, which helps it camouflage with the ocean floor. [6]
Opisthoteuthis pluto was originally described from material collected in the central Great Australian Bight, off southern Australia, and some additional material has been collected off southeastern Australia. The species is benthic and occurs over a depth range of approximately 250–823 m. [5] [4]
Grimpoteuthis is a genus of pelagic cirrate (finned) octopods known as the dumbo octopuses. The name "dumbo" originates from their resemblance to the title character of Disney's 1941 film Dumbo, having two prominent ear-like fins which extend from the mantle above each eye. There are 17 species recognized in the genus.
Umbrella octopuses are a group of pelagic octopuses. Umbrella octopuses are characterized by a web of skin between the arms, causing them to somewhat resemble an opened umbrella when the arms are spread.
Opisthoteuthis californiana, also known as the flapjack octopus, or flapjack devilfish is a species of umbrella octopus.
Stauroteuthis gilchristi is a species of small pelagic octopus found at great depths in the south Atlantic Ocean. It is believed to be one of a very small number of octopuses to exhibit bioluminescence, like its sister taxon Stauroteuthis syrtensis.
Cryptoteuthis brevibracchiata, the short-arm flapjack octopod, is a deepwater species of octopod. It is the only species in the monotypic genus Cryptoteuthis one of the cirrate octopuses of the family Grimpoteuthidae, the umbrella octopuses. It is known from a single specimen which was collected in the northeastern Atlantic Ocean. It has characteristics which are shared with two other genera, Opisthoteuthis and Grimpoteuthis, but is sufficiently distinctive from either of these to warrant the erection of a new genus.
Opisthoteuthis chathamensis, commonly known as the roughy umbrella octopus, is a species of cirrate octopus restricted to demersal habitats surrounding the Chatham Rise in New Zealand.
Opisthoteuthis agassizii is a lesser-known, deep-sea octopus first described in 1883 by Addison E. Verrill.
Opisthoteuthis albatrossi is a cirrate octopus originally found off Kinkasan in Japan. This species was described from only four specimens. It is similar to Opisthoteuthis californiana; the two may be the same species. It is also similar to Opisthoteuthis japonica.
Opisthoteuthis borealis is a lesser-known species of octopus found near Greenland and Iceland, especially in the Davis Strait. The species was described from 9 specimens, and is one of the most recent Opisthoteuthis species described. Not much is known about it besides its anatomy and habitat.
Opisthoteuthis bruuni is a species of finned cirrate octopus found along the western coast of South America. Their tissue is almost jelly-like, and they have short, round bodies.
Opisthoteuthis depressa, also known as the Japanese flapjack octopus, is an octopus found in waters near Japan.
Opisthoteuthis dongshaensis is a species of octopus located in the South China Sea.
Opisthoteuthis extensa is a species of octopus found off the west coast of Sumatra, an Indonesian island. It lives at a recorded depth of 768 m (2,520 ft). O. extensa lives in a benthic habitat, like many other cirrate octopuses. It occupies a deep part of the ocean where little sunlight penetrates.
Opisthoteuthis grimaldii is an octopus found near the Azores.
Opisthoteuthis hardyi is a lesser-known octopus species. It was described in 2002 from a male caught off the Shag Rocks, which are far south in the Atlantic Ocean near the Falkland Islands.
Opisthoteuthis massyae is an octopus living in the eastern Atlantic Ocean.
Opisthoteuthis medusoides is a cirrate octopus living off the coast of Tanzania near Dar es Salaam. However, its actual range may be more extensive.
Opisthoteuthis (Exsuperoteuthis) persephone is a cirrate octopus found off southern Australia. The species was described by S. Stillman Berry from eight specimens captured by the F.I.S. Endeavour in the early 1910s. In describing O. persephone, Berry called it an "exceedingly interesting octopod". The species has recently been redescribed and allocated as the type of genus Exsuperoteuthis.
Opisthoteuthis philipii is an octopus of the Indian Ocean. It lives off the coast of Kerala, India. Known specimens were found between 275–365 m (902–1,198 ft) deep in the Arabian Sea near Alappuzha.
Opisthoteuthis robsoni, also known as the deep-water umbrella octopus, is a deep-sea octopus living off New Zealand on the Chatham Rise. It has been found from 1,178–1,723 m (3,865–5,653 ft) below the surface. Not much is known about the octopus' habitat or life cycle, as only four specimens have been found. It occupies the benthic zone, or the seafloor and the water directly above it. O. robsoni eats large amphipods.