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Grendelius Scale
''Grendelius'' is a genus of platypterygiine ophthalmosaurid ichthyosaur from the Late Jurassic ( Kimmeridgian-Tithonian) of the UK and European Russia. It was a medium-sized ichthyosaur measuring about long. Taxonomy The type species, ''Grendelius mordax'', was described in 1976 on the basis of CAMSM J.68516, a complete skull with associated postcranial elements from the Kimmeridge Clay of England. Later, it was reassigned to ''Brachypterygius'' because differences between the two species were considered insufficient to warrant separate genera, or even species.McGowan, C. 1997. The taxonomic status of Grendelius mordax: a preliminary report. Journal of Vertebrate Paleontology, 17, 428–430. doi:10.1080/02724634.1997.10010986McGowan, C. & Motani, R. Ichthyopterygia. In Sues, H.-D. (ed.) Handbook of Paleoherpetology, vol. 8. Verlag Dr. Friedrich Pfeil, Munich, 175 pp., 19 pls. Efimov, 1998 named a new genus of ichthyosaur, ''Otschevia pseudoscythica'' on the basis of a single ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Jurassic
The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 163.5 ± 1.0 to 145.0 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic strata.Owen 1987. In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age. In the past, ''Malm'' was also used to indicate the unit of geological time, but this usage is now discouraged to make a clear distinction between lithostratigraphic and geochronologic/chronostratigraphic units. Subdivisions The Late Jurassic is divided into three ages, which correspond with the three (faunal) stages of Upper Jurassic rock: Paleogeography During the Late Jurassic Epoch, Pangaea broke up into two supercontinents, Laurasia to the north, and Gondwana to the south. The result of this break-up was the spawning of the Atlantic Ocean. However, at this time, the Atlantic Ocean was relatively narrow. Life forms of the epoch This epoch is well known for many famous types of din ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophthalmosauria
Ophthalmosauridae is an extinct family of thunnosaur ichthyosaurs from the Middle Jurassic to the early Late Cretaceous (Bajocian - Cenomanian) worldwide. Almost all ichthyosaurs from the Middle Jurassic onwards belong to the family, until the extinction of ichthyosaurs in the early Late Cretaceous. Opthalmosaurids appeared worldwide during early Bajocian, subsequent to the disappearance of most other ichthyosaur lineages after the end of the Toarcian. Currently, the oldest known ophthalmosaurids is ''Mollesaurus'' from the early Bajocian of Argentina, as well as indeterminate remains of the same age from Luxembourg and Canada. Named by George H. Baur, in 1887, the family contains the basal taxa like ''Ophthalmosaurus''. Appleby (1956) named the taxon Ophthalmosauria which was followed by some authors, but these two names are often treated as synonyms; Ophthalmosauridae has the priority over Ophthalmosauria. However, some researchers argue that Ophthalmosauridae should be restrict ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leninia Stellans
''Leninia'' is an extinct genus of basal ophthalmosaurine ichthyosaur known from the late Early Cretaceous (lower Aptian stage) of western Russia. ''Leninia'' was first named by Valentin Fischer, Maxim S. Arkhangelsky, Gleb N. Uspensky, Ilya M. Stenshin and Pascal Godefroit in 2013 and the type species is ''Leninia stellans''. It was named for Vladimir Lenin, one of the leaders of the Communist Revolution in Russia, as the museum it is currently housed in is also named for him. The specimen was discovered in 2012, on the banks of the river Volga near the town of Kriushi in a limestone nodule. There are several other fossils from the same time period near it, including ammonites, lamellibranchs and fish remains. Only part of the skull was found. Features The skull is incomplete, and without any teeth. it is partially crushed transversely, and nothing further forward than the naris remains, with what seems to be a fairly clean break. It is not known whether this was due to oro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muiscasaurus Catheti
''Muiscasaurus'' is an extinct genus of ophthalmosaurid Ichthyosaur that lived in modern Colombia during the Early Cretaceous. The only known species is the type ''Muiscasaurus catheti''. Discovery The fossils of ''Muiscasaurus'' were found in the Paja Formation, whose sediments are exposed near the town of Villa de Leyva in Boyacá Department. These remains were found in 2010 in the middle of a limestone concretion, known as the Arcillolitas abigarradas Member, dating from the Barremian to Aptian epochs of the Lower Cretaceous. Although ammonites were found attached to the fossils, their poor preservation prevented identifying them and thereby establish the stratigraphy and precise age of the specimen. The fossil found, listed as the holotype specimen CIP-FCG-CBP-74, consists of a partial skull and some vertebrae with ribs that were found associated with the skull. These remains were designated in 2015 as the new genus and species ''Muiscasaurus catheti''; the genus name bein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aegirosaurus Leptospondylus
''Aegirosaurus'' is an extinct genus of platypterygiine ophthalmosaurid ichthyosaurs known from the late Jurassic and early Cretaceous of Europe. It was originally named as a species of ''Ichthyosaurus''. Discovery and species Originally described by Wagner (1853) as a species of the genus ''Ichthyosaurus'' (''I. leptospondylus''), the species ''Aegirosaurus leptospondylus'' has had an unstable taxonomic history. It has been referred to the species '' Ichthyosaurus trigonus posthumus'' (later reclassified in the dubious genus ''Macropterygius'') in the past, and sometimes identified with ''Brachypterygius extremus''. In 2000, Bardet and Fernández selected a complete skeleton in a private collection as the neotype for the species ''I. leptospondylus'', as the only other described specimen was destroyed in World War II. A second specimen from the Munich collection was referred to the same taxon. Bardet and Fernández concluded that the neotype should be assigned to a new genus, ''A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brachypterygius Extremus
''Brachypterygius'' (meaning ″short wing/paddle″ in Greek) is an extinct genus of platypterygiine ophthalmosaurid ichthyosaur known from the Late Jurassic of England.McGowan, C. & Motani, R. ''Ichthyopterygia''. In Sues, H.-D. (ed.) Handbook of Paleoherpetology, vol. 8. Verlag Dr. Friedrich Pfeil, Munich, 175 pp., 19 pls. The type species was originally described and named as ''Ichthyosaurus extremus'' by Boulenger in 1904.Boulenger, G. A. 1904. Exhibition of, and remarks upon, a paddle of a new species of ichthyosaur. ''Proceedings of the Zoological Society of London'', 1904, 424–426. ''Brachypterygius'' was named by Huene in 1922 for the width and shortness of the forepaddle, and the type species is therefore ''Brachypterygius extremus''.Huene, F. F. von 1922. ''Die Ichthyosaurier des Lias und ihre Zusammenhänge''. Verlag von Gebrüder Borntraeger, Berlin, 114 pp., 22 pls. The holotype of ''B. extremus'' was originally thought to be from the Lias Group of Bath, United Ki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platypterygiinae
Platypterygiinae is an extinct subfamily of ophthalmosaurid thunnosaur ichthyosaurs from the early Late Jurassic to the early Late Cretaceous (Kimmeridgian - Cenomanian) of Asia, Australia, Europe, North America and South America. Currently, the oldest known platypterygiine is '' Brachypterygius''. Platypterygiines were characterized by square tooth roots in cross-section, an extremely reduced extracondylar area of the basioccipital, prominent dorsal and ventral trochanters on humerus and ischiopubis lacking an obturator foramen. Phylogeny Platypterygiinae was named in 2001 by Maxim S. Arkhangelsky and dually noted by colleague Aleski Masluk. It is a stem-based taxon defined phylogenetically for the first time by Fischer ''et al.'' (2012) as "all taxa closer to ''Platypterygius hercynicus'' than to ''Ophthalmosaurus icenicus''". The cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations amon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropterygius
''Arthropterygius'' is a widespread genus of ophthalmosaurid ichthyosaur which existed in Canada, Norway, Russia, and Argentina from the late Jurassic period and possibly to the earliest Cretaceous. Description ''Arthropterygius'' appears to have been a relatively large ichthyosaur, with all species measuring between long. The partially preserved specimen PMO 222.655 has been estimated at based on comparisons to the contemporary ophthalmosaurid '' Undorosaurus''. This specimen was probably mature or close to maturity at time of death, judging by the convex head of the humerus and the smooth texture of the humeral shaft. Skull and axial skeleton The skull of ''Arthropterygius'' has become well known due to the discovery of a well preserved skull from Svalbard. It is unusual among ichthyosaurs in having a very short, yet also robust rostrum for its skull length. As a result, the orbit appears very large (about 0.34× the skull length). The skull bears a very large pineal for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nannopterygius
''Nannopterygius'' (meaning "small wing/flipper" in Greek) is an extinct genus of ophthalmosaurid ichthyosaur that lived during the Middle Jurassic to the Early Cretaceous (Callovian to Berriasian stages). Fossils are known from England, Kazakhstan, Russia, and NorwayMcGowan, C. & Motani, R. (2003). ''Ichthyopterygia''. ''In'' Sues, H.-D. Handbook of Paleoherpetology, vol. 8. Verlag Dr. Friedrich Pfeil, Munich, 175 pp., 19pls. and six species are currently assigned to the genus. Description ''Nannopterygius'' was small for an ichthyosaur, measuring up to long at maximum. About of this was tail, including a deeply forked and probably homocercal caudal fin. The head is long, with a typical long narrow rostrum. The eyes are large, hence its classification as an ophthalmosaurid, and have a bony sclerotic ring inside the eye socket. There are at least 60 disc-shaped vertebrae, although owing to the condition of the fossil it is not possible to tell exactly how many there were, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gengasaurus Nicosiai
''Gengasaurus'' is an extinct genus of ophthalmosaurid ichthyosaur from the Jurassic. The type and only species, ''Gengasaurus nicosiai'', was named in 2017, after the locality of Genga, Marche. It lived in Italy about 152 million years ago. History The near complete holotype was discovered in 1976 in the Late Jurassic (Tithonian) Calcari ad aptici e Saccocoma Formation The Calcari ad aptici e Saccocoma Formation, also known as the Saccocoma Formation (known in English as the Haptic limestones and Saccocoma Formation), is a geologic formation in Camponocecchio, Italy that dates back to the Tithonian (152 Ma) - it ... at Camponocecchio and it was described in 1980 and 2000 as the "Genga ichthyosaur" before it was named and described in 2016Ilaria Paparella, Erin E. Maxwell, Angelo Cipriani, Scilla Roncacè and Michael W. Caldwell (2016) - The first ophthalmosaurid ichthyosaur from the Upper Jurassic of the Umbrian–Marchean Apennines (Marche, Central Italy). ''Geological Maga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophthalmosaurus Icenicus
''Ophthalmosaurus'' (meaning "eye lizard" in Greek) is an ichthyosaur of the Jurassic period (165–150 million years ago). Possible remains from the Cretaceous, around 145 million years ago, are also known. It was a relatively medium-sized ichthyosaur, measuring long and weighing . Named for its extremely large eyes, it had a jaw containing many small but robust teeth. Major fossil finds of this genus have been recorded in Europe with a second species possibly being found in North America. Description ''Ophthalmosaurus'' was a medium-sized ichthyosaur, measuring long and weighing . It had a robust, streamlined body that was nearly as wide as it was tall in frontal view. Like other derived ichthyosaurs ''Ophthalmosaurus'' had a powerful tail ending in a pronounced bi-lobed caudal fluke whose lower half was formed around the caudal spine whereas the upper lobe was made up entirely from soft tissue. The limbs of ''Ophthalmosaurus'' were short and rounded with the forelimbs bein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophthalmosaurus Natans
''Baptanodon'' is an ichthyosaur of the Late Jurassic period (160-156 million years ago), named for its supposed lack of teeth (although teeth of this genus have since been discovered). It had a graceful long dolphin-shaped body, and its jaws were well adapted for catching squid. Major fossil finds of this genus have been recorded in North America. The type species, ''Sauranodon natans'', was originally included under ''Sauranodon'' in 1879,O. C. Marsh. 1879. A new order of extinct reptiles (Sauranodonta), from the Jurassic Formation of the Rocky Mountains. ''The American Journal of Science and Arts, series 3'' but this name was preoccupied. Discovery and species ''Baptanodon'' is a replacement name for ''Sauranodon'' applied to ichthyosaur material in 1879 and was moved to its own genus ''Baptanodon'' in 1880 when ''Sauranodon'' was found to be preoccupied. ''Baptanodon'' was considered a junior synonym of '' Ophthalmosaurus'' by Maisch & Matzke (2000).Maisch MW, Matzke AT. 200 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
