Glowing sucker octopus | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Order: | Octopoda |
Family: | Stauroteuthidae |
Genus: | Stauroteuthis |
Species: | S. syrtensis |
Binomial name | |
Stauroteuthis syrtensis | |
Synonyms | |
|
Stauroteuthis syrtensis, also known as the glowing sucker octopus or bioluminescent octopus, is a species of small pelagic octopus found at great depths in the north Atlantic Ocean. It is one of a very small number of octopuses to exhibit bioluminescence. [3]
The cirrate octopuses are deep sea species that have been relatively little studied. Some have been described on the basis of a single, poorly preserved specimen, and this makes deducing their phylogenetic relationships difficult. [4] Some authorities adopt the traditional view that the genus Stauroteuthis is part of the family Stauroteuthidae that is characterized by the presence of a secondary web. [5] The World Register of Marine Species, however, considers that it should be placed in the family Cirroteuthidae, basing this decision on ribosomal DNA and other evidence, and that Stauroteuthidae is a synonym of this family. [2] [6] [7]
The mantle length of Stauroteuthis syrtensis is about 9 to 18 cm (4 to 7 in) and its width about 4 cm (1.6 in). Females typically display larger body sizes than the males, yet males exhibit wider and longer heads. [8] The fins are some 4 to 6 cm (1.6 to 2.4 in) in width. The eight arms are of unequal length, the longest extending to about 35 cm (14 in). These are joined for two-thirds of their length by two webs, a dorsal complete membrane and a ventral partial one, giving the animal an umbrella-like shape. The number of adhesive suckers ranges from 55 to 65. These suckers vary in size and distance among males and females. However, suckers generally decrease in diameter and distance as they extend down the arm. Female suckers reach a maximum diameter of 6.5 mm at suckers 1 to 3 while male suckers, on the other hand, are relatively larger. [9] Between suckers 8 to 25 there are conspicuous cirri. These are elongate, fleshy tendrils borne on the sides of the oral surface of the arms, the longest being at sucker 20 which can be up to 50 mm in length. [9] [10] The oral cavity and mouth area are pink or purple in color that extends towards the arms and lightens as it reaches the tips. [5] The general texture is gelatinous and the animal is reddish-brown and translucent, with the internal organs being visible through the skin. A vestigial, U-shaped, internal shell supports the fins, the only other hard part of the animal being the two-part beak. [11]
The diet of Stauroteuthis syrtensis consists mostly of crustaceans, with the majority belonging to groups such as calanoida, mysidacia, and occasionally isopoda. [8] Although observations of hunting and feeding behavior seem to be absent from the literature, Stauroteuthis syrtensis has been reported to float passively with arms contracted, webs curled into a ball, and eyes hooded, until disturbed by research submersibles. [5]
Stauroteuthis syrtensis is found in the North Atlantic at an extreme depth range of 500 to 4,000 m (1,600 to 13,100 ft). It is most frequently found a few hundred metres from the bottom of the ocean at depths between 1,500 and 2,500 m (4,900 and 8,200 ft). It seems to be fairly common off the edge of the continental shelf on the eastern coast of the United States, and has also been observed at similar depths off the British Isles. [10] The species is strongly restricted from crossing into the Arctic ocean, even where similar habitat (deep ocean ridges) exist. The strongest restriction factor to their northern range is assumed to be related to temperature [8]
Stauroteuthis is one of only two genera of octopuses to exhibit bioluminescence. [3] S. syrtensis emits a blue-green light from about 40 modified suckers known as photophores situated in a single row between the pairs of cirri on the underside of each arm. The distance between these decreases towards the ends of the arms with the light becoming fainter. The animal does not emit light continuously, but can do so for a period of five minutes after suitable stimulation. [3] Some of the photophores emit a continuous stream of faint light, while others are much brighter and switch on and off in a cyclical pattern, producing a twinkling effect. [3] The function of the bioluminescence is believed to be for defense, being used by the animal to scare off predators, and also as a lure for the planktonic crustaceans that form its main diet. [3] While some species, such as the Lampyris noctiluca use their light to attract a mate, the light may also be used for sexual signaling as well, but this is considered to be an unlikely function, as the light is deployed by both sexes and by immature, as well as mature, individuals. [3]
S. syrtensis is noted for inspiring self-adaptive, soft robotic grippers used for underwater handling of various objects. The gripper closely mimics the sucker and web structure of S. sytenesis, which is adapted for preying upon crustaceans of differing size and shape. The resulting robotic gripper is therefore superior for grasping round, concave, flat, or irregularly shaped objects when visibility is low or conditions are turbid. [12]
Another innovation inspired by the glowing sucker octopus are self-healing, photoswitchable and reversible fluorescent eutectogels. [13] These are stimulus responsive (typically by UV radiation) materials with tunable florescence that can be used to write unique patterns. Their self-healing properties, and resistance to stresses such as stretching make them a promising material for use in anti-counterfeiting, and information encryption measures.
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.
Luteuthis dentatus, also known as Lu's jellyhead, is a medium-sized species of cirrate octopus found in the southwestern Pacific, originally described by Steve O'Shea.
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.
The Bolitaeninae are a subfamily, in the family Amphitretidae, of small, common pelagic octopuses found in all tropical and temperate oceans of the world. The taxonomy of this taxon is not entirely certain; recent research suggests just two genera exist, Bolitaena and Japetella, both of which are thought to be monotypic by some authorities and under this view, the family would represent two very similar species: Bolitaena pygmaea and Japetella diaphana. However, currently a second species of Bolitaena, B. massyae is also recognised.
Teuthology is the study of cephalopods. Cephalopods are members of the class Cephalopoda in the Phylum Mollusca. Some common examples of cephalopods are octopus, squid, and cuttlefish. Teuthology is a large area of study that covers cephalopod life cycles, reproduction, evolution, anatomy and taxonomy.
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.
Incirrata is a suborder of the order Octopoda. The suborder contains the classic "benthic octopuses," as well as many pelagic octopus families, including the paper nautiluses. The incirrate octopuses are distinguished from the cirrate octopuses by the absence in the former of the "cirri" filaments for which the cirrates are named, as well as by the lack of paired swimming fins on the head, and lack of a small internal shell.
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.
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.
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.
Luteuthis is a small genus of cirrate octopuses currently placed in the family Grimpoteuthidae. There are two species classified in this genus one from waters west of New Zealand and the other from the South China Sea.
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.
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 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".
Grimpoteuthis greeni is a dumbo octopus found in deep waters off southern Australia. The species was initially described from three specimens, with a further three specimens identified since then.
Stauroteuthis kengrahami is a species of small pelagic cirrate octopus. It is currently only known from off eastern Australia.