| Luteuthis | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Order: | Octopoda |
| Family: | Grimpoteuthidae |
| Genus: | Luteuthis O'Shea, 1999 [1] |
| Type species | |
| Luteuthis dentatus O'Shea, 1999 | |
| Species | |
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.
Luteuthis are characterized by several unique features. The body is relatively elongate, extensively gelatinous and lacking areolar spots. The paired fins are laterally placed, and supported by a W-shaped internal shell with the shell wings bearing in-rolled margins and tapering to acute points. The arms are narrow and connected by simple webbing, there is no web nodule acting as a web attachment point. The suckers are crenulated (around the aperture opening) and are flanked by rows of short cirri (cirri about half as long as the sucker diameter). The gills resemble a "half-orange" and have seven lamellae. Luteuthis species have a well developed radula as well as palatine teeth on the palps flanking the radula, and the digestive gland is bilobed. [2] [3] As with other cirrate octopods, the ink sac is missing. [2]
The genus was originally placed within its own family, Luteuthidae (O'Shea, 1999), as the presence of a radula was deemed very distinctive. However, it later became apparent that species of Grimpoteuthis also often have a radula and the two genera share other distinctive features (such as the optic nerves forming a single bundle each side of the head), with molecular data further supporting placement of Luteuthis, Grimpoteuthis and Cryptoteuthis in the family Grimpoteuthidae [2] [4] .
The two species in the genus Luteuthis are: [1]
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 a prominent ear-like fin which extends 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 to 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.
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.
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.
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.
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.
Grimpoteuthis abyssicola, commonly known as the red jellyhead, is a species of small deep-sea octopus known from two specimens. The holotype specimen was a female collected on the Lord Howe Rise, between 3154 and 3180 meters depth. A second specimen was collected on the continental slope of south-eastern Australia between 2821 and 2687 m depth. While the organism has not been formally assigned a vernacular name, it has been proposed to be referred to commonly as the angle-shelled dumbo octopus.
Grimpoteuthis boylei is a species of octopus known from only ten individuals.
Grimpoteuthis plena is known from only one specimen, which cannot be easily separated from other species of Grimpoteuthis in the Atlantic Ocean. The specimen was in poor condition. It's similar to Grimpoteuthis wuelkeri, and may be a junior specimen of Grimpoteuthis umbellata.
Opisthoteuthis agassizii, known as the Agassiz's flapjack octopus, 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 grimaldii is an octopus found near the Azores.
Opisthoteuths massyae is an octopus living in the eastern Atlantic Ocean.
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.
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.
Dumbo octopuses are a group of bentho-pelagic octopuses, comprising three currently accepted genera. They have extensive arm webbing and relatively large fins allowing for powerful fin swimming.