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 as well as the eighth period of the Phanerozoic Eon and is named after the Jura Mountains, where limestone strata from the period were first identified.
Ichthyosauria is an order of large extinct marine reptiles sometimes referred to as "ichthyosaurs", although the term is also used for wider clades in which the order resides.
The Early Jurassic Epoch is the earliest of three epochs of the Jurassic Period. The Early Jurassic starts immediately after the Triassic–Jurassic extinction event, 201.3 Ma, and ends at the start of the Middle Jurassic 174.7 ±0.8 Ma.
Ichthyosaurus is a genus of ichthyosaurs from the Early Jurassic of Europe. Some specimens of the ichthyosaurid Protoichthyosaurus from England and Switzerland have been erroneously referred to this genus in the past. It is among the best known ichthyosaur genera, as it is the type genus of the order Ichthyosauria.
Temnodontosaurus is an extinct genus of ichthyosaur from the Early Jurassic period. They lived between 200 and 175 million years ago (Hettangian-Toarcian) in what is now Western Europe and possibly other countries including Switzerland and Chile. It lived in the deeper areas of the open ocean. University of Bristol paleontologist Jeremy Martin described the genus Temnodontosaurus as "one of the most ecologically disparate genera of ichthyosaurs," although the number of valid Temnodontosaurus species has varied over the years.
Sarcosaurus is a genus of basal neotheropod dinosaur, roughly 3.5 metres (11 ft) long. It lived in what is now England and maybe Ireland and Scotland during the Hettangian-Sinemurian stages of the Early Jurassic, about 199-196 million years ago. Sarcosaurus is one of the earliest known Jurassic theropods, and one of only a handful of theropod genera from this time period. Along with Dracoraptor hanigani it is one of the two described neotheropods from the lowermost Jurassic of the United Kingdom.
Dapedium is an extinct genus of primitive marine neopterygian ray-finned fish. The first-described finding was an example of D. politum, found in the Lower Lias of Lyme Regis, on the Jurassic Coast of England. Dapedium lived in the Late Triassic to the Middle Jurassic period, from the late Norian to the early Aalenian.
Thalassiodracon (tha-LAS-ee-o-DRAY-kon) is an extinct genus of plesiosauroid from the Pliosauridae that was alive during the Late Triassic-Early Jurassic (Rhaetian-Hettangian) and is known exclusively from the Lower Lias of England. The type and only species, is Thalassiodracon (Plesiosaurus) hawkinsii.
Chacaicosaurus is a genus of neoichthyosaurian ichthyosaur known from the Middle Jurassic of Argentina. The single known specimen of this genus was excavated from the Los Molles Formation in Neuquén Province, and is housed at the Museo Olsacher under the specimen number MOZ 5803. This specimen consists of a skull, forelimb, some vertebrae, and some additional postcranial elements. The genus was named by Marta Fernández in 1994, and contains a single species, Chacaicosaurus cayi, making it the first named distinctive ichthyosaur from the Bajocian stage. It is a medium-sized ichthyosaur with a very long snout, which bears a ridge running along each side. The forelimbs of Chacaicosaurus are small and contain four main digits.
The Elliot Formation is a geological formation and forms part of the Stormberg Group, the uppermost geological group that comprises the greater Karoo Supergroup. Outcrops of the Elliot Formation have been found in the northern Eastern Cape, southern Free State, and in the eastern KwaZulu-Natal provinces of South Africa. Outcrops and exposures are also found in several localities in Lesotho such as Qacha's Neck, Hill Top, Quthing, and near the capital, Maseru. The Elliot Formation is further divided into the lower (LEF) and upper (UEF) Elliot formations to differentiate significant sedimentological differences between these layers. The LEF is dominantly Late Triassic (Norian-Hettangian) in age while the UEF is mainly Early Jurassic (Sinemurian-Pliensbachian) and is tentatively regarded to preserve a continental record of the Triassic-Jurassic boundary in southern Africa. This geological formation is named after the town of Elliot in the Eastern Cape, and its stratotype locality is located on the Barkly Pass, 9 km north of the town.
Clevosaurus is an extinct genus of rhynchocephalian reptile from the Late Triassic and the Early Jurassic periods. Species of Clevosaurus were widespread across Pangaea, and have been found on all continents except Australia and Antarctica. Five species of Clevosaurus have been found in ancient fissure fill deposits in south-west England and Wales, alongside other sphenodontians, early mammals and dinosaurs. In regards to its Pangaean distribution, C. hadroprodon is the oldest record of a sphenodontian from Gondwana, though its affinity to Clevosaurus has been questioned.
The Blue Lias is a geological formation in southern, eastern and western England and parts of South Wales, part of the Lias Group. The Blue Lias consists of a sequence of limestone and shale layers, laid down in latest Triassic and early Jurassic times, between 195 and 200 million years ago. The Blue Lias is famous for its fossils, especially ammonites.
Eurycleidus is an extinct genus of large-bodied rhomaleosaurid known from the Early Jurassic period of the United Kingdom. It contains a single species, E. arcuatus.
The Whitby Mudstone is a Toarcian geological formation in Yorkshire and Worcestershire, England. The formation, part of the Lias Group, is present in the Cleveland and Worcester Basins and the East Midlands Shelf.
Eoplesiosaurus is an extinct genus of basal plesiosauroid known from the Early Jurassic period of the United Kingdom. It contains a single species, E. antiquior.
Waterloo Bay is an area of foreshore in Larne on the east coast of County Antrim, Northern Ireland. It is of particular interest to geologists because it provides a clear, complete and accessible example of the sequences from Upper Triassic to Lower Jurassic, when the rock types changed from land to marine.
The Charmouth Mudstone Formation is a geological formation in England, dating to the Early Jurassic (Sinemurian–Pliensbachian). It forms part of the lower Lias Group. It is most prominently exposed at its type locality in cliff section between Lyme Regis and Charmouth but onshore it extends northwards to Market Weighton, Yorkshire, and in the subsurface of the East Midlands Shelf and Wessex Basin. The formation is notable for its fossils, including those of ammonites and marine reptiles and rare dinosaur remains. The formation played a prominent role in the history of early paleontology, with its Lyme Regis-Charmouth exposure being frequented by fossil collectors including Mary Anning.
This timeline of ichthyosaur research is a chronological listing of events in the history of paleontology focused on the ichthyosauromorphs, a group of secondarily aquatic marine reptiles whose later members superficially resembled dolphins, sharks, or swordfish. Scientists have documented ichthyosaur fossils at least as far back as the late 17th century. At that time, a scholar named Edward Lhuyd published a book on British fossils that misattributed some ichthyosaur vertebrae to actual fishes; their true nature was not recognized until the 19th century. In 1811, a boy named Joseph Anning discovered the first ichthyosaur fossils that would come to be scientifically recognized as such. His sister, Mary Anning, would later find the rest of its skeleton and would go on to become a respected fossil collector and paleontologist in her own right.
Wahlisaurus is an extinct genus of leptonectid ichthyosaur from the Scunthorpe Mudstone of England. The type species is Wahlisaurus massarae, and two specimens have been found: the first consisting of a skull and an incomplete skeleton, and the second a single coracoid.
This list of fossil reptiles described in 2021 is a list of new taxa of fossil reptiles that were described during the year 2021, as well as other significant discoveries and events related to reptile paleontology that occurred in 2021.
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