Necroteuthis Temporal range: | |
---|---|
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Order: | Vampyromorphida |
Family: | Vampyroteuthidae |
Genus: | † Necroteuthis Kretzoi, 1942 [1] |
Species: | †N. hungarica |
Binomial name | |
†Necroteuthis hungarica Kretzoi, 1942 | |
Necroteuthis is an extinct genus of vampire squids from the Oligocene of Hungary. It contains one species, N. hungarica. It was initially identified as a squid, [1] but was recently reinterpreted as a vampyroteuthid. [2]
The Oligocene is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present. As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from the Ancient Greek ὀλίγος and καινός, and refers to the sparsity of extant forms of molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene Epoch. The Oligocene is the third and final epoch of the Paleogene Period.
A squid is a mollusc with an elongated soft body, large eyes, eight arms, and two tentacles in the superorder Decapodiformes, though many other molluscs within the broader Neocoleoidea are also called squid despite not strictly fitting these criteria. Like all other cephalopods, squid have a distinct head, bilateral symmetry, and a mantle. They are mainly soft-bodied, like octopuses, but have a small internal skeleton in the form of a rod-like gladius or pen, made of chitin.
A cephalopod is any member of the molluscan class Cephalopoda such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles modified from the primitive molluscan foot. Fishers sometimes call cephalopods "inkfish", referring to their common ability to squirt ink. The study of cephalopods is a branch of malacology known as teuthology.
The vampire squid is a small cephalopod found throughout temperate and tropical oceans in extreme deep sea conditions. The vampire squid uses its bioluminescent organs and its unique oxygen metabolism to thrive in the parts of the ocean with the lowest concentrations of oxygen. It has two long retractile filaments, located between the first two pairs of arms on its dorsal side, which distinguish it from both octopuses and squids, and places it in its own order, Vampyromorphida, although its closest relatives are octopods. As a phylogenetic relict, it is the only known surviving member of its order.
Vampyroteuthidae is a family of vampyromorph cephalopods containing the extant vampire squid, Vampyroteuthis infernalis, and the extinct genera Necroteuthis, Provampyroteuthis, and Vampyronassa.
Vampyromorphida is an order of cephalopods comprising one known extant species and many extinct taxa. Physically, they somewhat resemble octopuses, but are often called vampire squids. Unlike octopi, their eight arms are united by a web of skin, and two smaller cilia are also present. Properly speaking, the vampire squid does not possess cilia, but cirri.
Nothofagus, also known as the southern beeches, is a genus of 43 species of trees and shrubs native to the Southern Hemisphere in southern South America and east and southeast Australia, New Zealand, New Guinea, and New Caledonia. The species are ecological dominants in many temperate forests in these regions. Some species are reportedly naturalised in Germany and Great Britain. The genus has a rich fossil record of leaves, cupules, and pollen, with fossils extending into the late Cretaceous period and occurring in Australia, New Zealand, Antarctica, and South America.
Subclass Coleoidea, or Dibranchiata, is the grouping of cephalopods containing all the various taxa popularly thought of as "soft-bodied" or "shell-less". Unlike its extant sister group, Nautiloidea, whose members have a rigid outer shell for protection, the coleoids have at most an internal cuttlebone, gladius, or shell that is used for buoyancy or support. Some species have lost their cuttlebone altogether, while in some it has been replaced by a chitinous support structure. A unique trait of the group is the ability to edit their own RNA.
Bigfin squids are a group of rarely seen cephalopods with a distinctive morphology. They are placed in the genus Magnapinna and family Magnapinnidae. Although the family was described only from larval, paralarval, and juvenile specimens, numerous video observations of larger squid with similar morphology are assumed to be adult specimens of the same family.
Albatrosses, of the biological family Diomedeidae, are large seabirds related to the procellariids, storm petrels, and diving petrels in the order Procellariiformes. They range widely in the Southern Ocean and the North Pacific. They are absent from the North Atlantic, although fossil remains show they once occurred there and occasional vagrants are found. Albatrosses are among the largest of flying birds, and species of the genus Diomedea have the longest wingspans of any extant birds, reaching up to 3.7 m (12 ft). The albatrosses are usually regarded as falling into four genera, but disagreement exists over the number of species.
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.
Octopodiformes is a superorder of the subclass Coleoidea, comprising the octopuses and the vampire squid. All living members of Octopodiformes have eight arms, either lacking the two tentacles of squid or modifying the tentacles into thin filaments. Octopodiformes is often considered the crown group of octopuses and vampire squids, including all descendants of their common ancestor. Some authors use the term Vampyropoda for the same general category, though others use "Vampyropoda" to refer to the total group. Another term is Octobranchia, referring to cephalopods without prominent tentacles.
Cephalopods, which include squids and octopuses, vary enormously in size. The smallest are only about 1 centimetre (0.39 in) long and weigh less than 1 gram (0.035 oz) at maturity, while the largest—the giant and colossal squids—can exceed 10 metres (33 ft) in length and weigh close to half a tonne (1,100 lb), making them the largest living invertebrates. Living species range in mass more than three-billion-fold, or across nine orders of magnitude, from the lightest hatchlings to the heaviest adults. Certain cephalopod species are also noted for having individual body parts of exceptional size. The giant and colossal squids, for example, have the largest known eyes among living animals.
Vampyronassa rhodanica is an extinct vampyromorph cephalopod known from around 20 fossils from the Lower Callovian of La Voulte-sur-Rhône, Ardèche, France.
The colossal squid is part of the family Cranchiidae. It is sometimes called the Antarctic squid or giant cranch squid and is believed to be the largest squid species in terms of mass. It is the only recognized member of the genus Mesonychoteuthis and is known from only a small number of specimens. The species is confirmed to reach a mass of at least 495 kilograms (1,091 lb), though the largest specimens—known only from beaks found in sperm whale stomachs—may perhaps weigh as much as 600–700 kilograms (1,300–1,500 lb), making it the largest known invertebrate. Maximum total length has been estimated at 9–10 metres (30–33 ft). The colossal squid has the largest eyes of any known creature ever to exist, with an estimated diameter of 27 cm (11 in).
Neocoleoidea is a large group of marine cephalopods. This cohort contains two extant groups: Decapodiformes and Octopodiformes. Species within this group exist in all major habitats in the ocean, in both the southern and northern polar regions, and from intertidal zones to great depths. Whilst conventionally held to be monophyletic, the only morphological character for the group is the presence of suckers: although the presence of these features in the belemnites suggests that they do not support the Neocoleoidea, and hence that the group may be paraphyletic.
Kamoyapithecus was a primate that lived in Africa during the late Oligocene period, about 24.2-27.5 million years ago. First found in 1948 as part of a University of California, Berkeley expedition, it was at first thought to be under a form of Proconsul by C.T. Madden in 1980, but after a re-examination by Meave Leakey and associates later, the fossils were moved under a new genus Kamoyapithecus, named after the renowned fossil finder Kamoya Kimeu. The genus is represented by only one species, K. hamiltoni.
Cephalopod fins, sometimes known as wings, are paired flap-like locomotory appendages. They are found in ten-limbed cephalopods as well as in the eight-limbed cirrate octopuses and vampire squid. Many extinct cephalopod groups also possessed fins. Nautiluses and the more familiar incirrate octopuses lack swimming fins. An extreme development of the cephalopod fin is seen in the bigfin squid of the family Magnapinnidae.
Opisthoteuthis is a genus of cirrate octopuses, sometimes known as flapjack octopuses, which are found in all the world's oceans.
Richard E. Young is a teuthologist. He is an Emeritus Professor of Oceanography at the University of Hawaii's School of Ocean and Earth Science and Technology.