The Jurassic is a geologic period and stratigraphic system that spanned from the end of the Triassic Period 201.4 million years ago (Mya) to the beginning of the Cretaceous Period, approximately 145 Mya. The Jurassic constitutes the middle period of the Mesozoic Era and is named after the Jura Mountains, where limestone strata from the period were first identified.
An octopus is a soft-bodied, eight-limbed mollusc of the order Octopoda. The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids. Like other cephalopods, an octopus is bilaterally symmetric with two eyes and a beaked mouth at the center point of the eight limbs. The soft body can radically alter its shape, enabling octopuses to squeeze through small gaps. They trail their eight appendages behind them as they swim. The siphon is used both for respiration and for locomotion, by expelling a jet of water. Octopuses have a complex nervous system and excellent sight, and are among the most intelligent and behaviourally diverse of all invertebrates.
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 Some species have lost their cuttlebone altogether, while in some it has been replaced by a chitinous support structure.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.
Hypsocormus is an extinct genus of pachycormid fish from the Middle to Late Jurassic of Europe. Fossils have been found in Germany, France and the UK.
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.
Pohlsepia mazonensis is a species of fossil organism with unknown affinity. Although it was originally identified as an extinct cephalopod, later studies denied that interpretation. The species is known from a single exceptionally preserved fossil discovered in the late Carboniferous (Pennsylvanian) Francis Creek Shale of the Carbondale Formation, north-east Illinois, United States.
Palaeoctopus newboldi is an extinct basal octopod that lived in the Late Cretaceous, approximately 89 to 71 million years ago. Fossil material assigned to this species originates from the Mount Hajoula region in Lebanon. The holotype was found below the Old Covent, Sahel-el-Alma, Mount Lebanon and is deposited at the Natural History Museum in London. It might belong to the Cirrina or be more basal in the Octopoda. Specimens from the Turonian of Vallecino, Mexico, originally described as P. pelagicus, are reinterpreted to be portions of a coelacanth.
Tusoteuthis is an extinct genus of large enchoteuthine cephalopod that lived during the Cretaceous. Although often called a squid, it is now thought to be more closely related to modern octopuses. Examination of gladius remains has yielded an estimated mantle length close to or equal to that of the modern giant squid. Fossil remains have been found in parts of the one-time Western Interior Seaway of North America, including Late Cretaceous rocks in Kansas, Colorado, Wyoming, South Dakota, North Dakota, and Manitoba Province. One species, T. longa, is traditionally recognized. In 2019, due to poor preservation of holotype specimen, genus Tusoteuthis is likely to be invalid, and it is considered that later described species are better to include in genus Enchoteuthis instead.
Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 2009.
Styletoctopus is an extinct genus of octopus. The genus consists of the single species Styletoctopus annae, which lived approximately 95 million years ago. Very few octopus species appear in the fossil record, as octopuses consist of soft tissue that usually decomposes before it has time to fossilize.
Orthocormus is an extinct genus of prehistoric pachycormiform bony fish. It is known from three species found in Late Jurassic (Kimmeridgian) aged plattenkalk deposits in Bavaria, Germany. The species "Hypsocormus" tenuirostris Woodward 1889 from the late Middle Jurassic (Callovian) Oxford Clay is not closely related to the type species of Hypsocormus, and is more closely related to Orthocormus + Protosphyraena, and thus has sometimes been referred to in open nomenclature as Orthocormus? tenuirostris.
Acanthochirana is an extinct genus of prawn that existed during the upper Jurassic period. It was named by E. Strand in 1928, and its type species is Acanthochirana cordata. They are distinguished from the related genus Aeger by the presence of teeth on the rostrum, which are absent in Aeger.
Belemnitida is an extinct order of squid-like cephalopods that existed from the Late Triassic to Late Cretaceous. Unlike squid, belemnites had an internal skeleton that made up the cone. The parts are, from the arms-most to the tip: the tongue-shaped pro-ostracum, the conical phragmocone, and the pointy guard. The calcitic guard is the most common belemnite remain. Belemnites, in life, are thought to have had 10 hooked arms and a pair of fins on the guard. The chitinous hooks were usually no bigger than 5 mm (0.20 in), though a belemnite could have had between 100 and 800 hooks in total, using them to stab and hold onto prey.
Coleia is an extinct genus of decapods in the group Polychelida that lived from the Late Triassic to the Late Jurassic. It was described by Broderip in 1835, and the type species is C. antiqua. A new species, C. martinlutheri, which existed during the Sinemurian of what is now Germany, was described by Günter Schweigert and Werner Ernst in 2012.
This list, 2018 in paleomalacology, is a list of new taxa of ammonites and other fossil cephalopods, as well as fossil gastropods, bivalves and other molluscs that are scheduled to be described during the year 2018, as well as other significant discoveries and events related to molluscan paleontology that are scheduled to occur in the year 2018.
Muensterellidae is a family of stem-octopod cephalopods from the Late Jurassic to Late Cretaceous.
This list 2020 in paleomalacology is a list of new taxa of ammonites and other fossil cephalopods, as well as fossil gastropods, bivalves and other molluscs that are scheduled to be described during the year 2020, as well as other significant discoveries and events related to molluscan paleontology that are scheduled to occur in the year 2020.
Muensterelloidea is a superfamily of stem-octopod cephalopods from the Early Jurassic to Late Cretaceous. Two families are currently identified, Muensterellidae, and Patelloctopodidae. The clade is the ancestral group from which modern octopus arose.
Enchoteuthis is an extinct genus of large enchoteuthine cephalopod that lived during the Cretaceous. Although it and its relative Tusoteuthis are often compared to squid, both are now thought to be more closely related to modern octopuses. Examination of gladius remains initially yielded an estimated mantle length about 2 m based on specimen once described as Tusoteuthis longa, close to or equal to that of the modern giant squid, although reclassification of this genus as a muensterelloid results in a much shorter total length, about 3 m (10 ft). Three species are currently recognized as valid: E. melanae, E. tonii, and E. cobbani.
The Teudopseina is a clade of stem-octopods that first evolved in the Toarcian, considered the largest clade of gladius-bearing coleoids in the Mesozoic. Up to five families are known, among which the Trachyteuthidae, Trachyteuthis in particular, were the most abundant.
