Flapjack octopus | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Order: | Octopoda |
Family: | Opisthoteuthidae |
Genus: | Opisthoteuthis |
Species: | O. calypso |
Binomial name | |
Opisthoteuthis calypso Villanueva, Collins, Sánchez & Voss, 2002 | |
Opisthoteuthis calypso or calypso flapjack octopus is a species of genus Opisthoteuthis , which are known as the cirrate octopuses. Octopuses in this genus are known as the flapjack octopuses and can be found in a variety of oceans across the world. [1]
The species of this genus show distinctive characteristics among the class Cephalopoda, including an oval shaped body compressed along the longitudinal axis, a gelatinous consistence and a large interbarachil web.
This species generally has a mantle length of 5 cm. [2] [3] This web is what has given them their common name "flapjack" or "pancake devil fish". [4] Other distinctive features include the presence of two small fins on the mantle, an internal U-shaped shell that has a groove along its outer surface. This particular species has eight, subequal arms (of an uneven length). [5] As adults, they tend to have 47–58 suckers on each of these eight arms. Their cirri (small tassel-like appendages on the surface of the octopus) are on the shorter end, with a length reaching up to 5 mm. This is what differs them from other members of the Opisthoteuthis genus. [1] Due to the delicate consistency of the species, captured specimen are often in poor condition and therefore near impossible to identify other particular distinguishing features. [3]
This species is typically found in the South Eastern Atlantic Ocean and Mediterranean Sea, although they are quite rare and therefore distribution is not well known. In terms of habitat, the species has been found on muddy bottoms at depths of 365 meters in the South East Atlantic and 2208 meters in the Mediterranean. Recent studies have found 11 specimens around the Balearic Islands in the western Mediterranean, [6] and others 38 others have been found at depths ranging from 871 to 1420 meters in the Sardinian Channel of the central Western Mediterranean. [7] This species was previously mistaken for O. agassizi, a species in the same genus. [1] Since, previous captured specimen of O. agassizi, that were found in the Mediterranean have been accredited to O. calypso, and is now believed to be the sole Opisthoteuthis species in the area. [3]
Adult males are larger than females, with a total length of 482 mm and a weight of 5400 grams, while the females have a total length of 342 mm and a weight of 1650 g. [1] Females of the Opisthoteuthis calypso have been shown to have ovarian oocyte size frequency which is akin to species that show continuous egg production and release, alluding to a continuous-spawning reproductive pattern. This contrasts with the semelparity shown in a majority of incirrate octopuses. [3]
The prey of Opisthoteuthis calypso includes small organisms with slow swim speeds. The most important prey items for Opisthoteuthis calypso include benthic gammarid, amphipods, and polychaetes of the epibenthic fauna (those which live on or just above the bottom sediments). [1]
In samples taken from the Sardinian Channel, Polychaeta and Crustacea made up around 40% and 36% of the total stomach contents respectively. Sand was also found in the stomachs of all samples which alludes to further evidence of their hunting behavior taking place in epibenthic zones. [7] A detailed analysis feeding of relative species O. agassizi at 490 meters have shown a pattern of continuous feeding and is believed to be true for Opisthoteuthis calypso as well. [8] Visually oriented species such as this, who are living at greater depths show a decrease in energy expenditure rates as the depth increases. This decrease in energy usage is attributed to the reduction in locomotion needed with the visually instigated predator-prey relationship in the light-limited habitat they live in. [9]
This species of Opisthoteuthis is found to be on the vulnerable stage of the IUCN Red List of Threatened Species as of 2014. This species has been accessed as vulnerable because of impacts by the commercial fishing market as bycatch. Similar congeneric species with a similar biology to Opisthoteuthis calypso has been shown to decline by 30% over three generations due to similar reasoning. [10]
Cirroteuthidae is a family of pelagic cirrate octopuses comprising at least three species in two genera.
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. Prey include crustaceans, bivalves, worms and copepods. The average life span of various Grimpoteuthis species is 3–5 years.
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.
Stauroteuthis is a genus of deepwater cirrate octopus, a cephalopod mollusk. This is the only genus in the family Stauroteuthidae, and only three species have been described in this genus.
Opisthoteuthis californiana, also known as the flapjack octopus, or flapjack devilfish is a species of umbrella octopus.
Cirrina or Cirrata is a suborder and one of the two main divisions of octopuses. Cirrate octopuses have a small, internal shell and two fins on their head, while their sister suborder Incirrina has neither. The fins of cirrate octopods are associated with a unique cartilage-like shell in a shell sac. In cross-section, the fins have distinct proximal and distal regions, both of which are covered by a thin surface sheath of muscle.
Cirroteuthis muelleri, also known as the big-finned jellyhead, was the first cirrate octopus species to be scientifically described. It is closely related to the genus Cirrothauma within the family Cirroteuthidae. At present the genus contains a single recognized species restricted to the Arctic Ocean and northern basins of the Atlantic and Pacific, but other species may be present in the southern hemisphere.
Cirrate octopuses possess a well-developed internal shell that supports their muscular swimming fins. This is in contrast to the more familiar, finless, incirrate octopuses, in which the shell remnant is either present as a pair of stylets or absent altogether.
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 is a genus of cirrate octopuses, sometimes known as flapjack octopuses, which are found in all the world's oceans.
Opisthoteuthis agassizii is a lesser-known, deep-sea octopus first described in 1883 by Addison E. Verrill.
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 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.
Bathypolypus sponsalis, commonly called the globose octopus, is a deep sea cephalopod that can be found in both the eastern Atlantic Ocean and the Mediterranean Sea. It possesses many morphological traits adapted to a deep sea environment, including large eggs, reduced gills, no ink sac, and subgelatinous tissues. A distinguishing factor are the relatively large reproductive organs. Their diet consists of predominantly crustaceans and molluscs, but they sometimes consume fish as well. Bathypolypus sponsalis usually dies quickly after reproduction and only spawns once in their lifetime. Sexually mature females have a mantle length of at least 34 mm and sexually mature males have a mantle length of about 24 mm. Juveniles are white and transition to dark brown then to dark purple once maturity is reached.
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 persephone is a cirrate octopus living south of Australia. In particular, it lives in waters off Tasmania, Victoria, New South Wales, and South Australia. The octopus has been found 270–540 m (885.8–1,771.7 ft) deep. It lives near and directly above the seafloor. S. Stillman Berry was the first to scientifically describe this species after capturing eight specimens while aboard the F.I.S. Endeavour in the early 1910s. In describing O. persephone, Berry called it an "exceedingly interesting octopod".
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.