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Sveltonectes
''Sveltonectes'' (meaning "agile swimmer" in Greek) is an extinct genus of platypterygiine ophthalmosaurid ichthyosaurs known from Ul’yanovsk region, western Russia. Etymology ''Sveltonectes'' was named by Valentin Fischer, Edwige Masure, Maxim S. Arkhangelsky, and Pascal Godefroit in 2011 in paleontology, 2011 and the type species is ''Sveltonectes insolitus''. The name of a biological genus, generic name is derived from ''sveltos'', Greek language, Greek for "agile", and ''nektes'', Greek for "swimmer", and refers to its small size, streamlined skull, and powerful girdle musculature. The specific name (zoology), specific name is derived from ''insolitus'', Latin for "unusual", in reference to the numerous unusual features of this ichthyosaur, as well as its unusual tooth morphology. Description ''Sveltonectes'' is known from the holotype Royal Belgian Institute of Natural Sciences, IRSNB R269, an almost complete three-dimensionally preserved skeleton including a partial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acamptonectes
''Acamptonectes'' is a genus of ophthalmosaurid ichthyosaurs, a type of dolphin-like marine reptiles, that lived during the Early Cretaceous around 130 million years ago. The first specimen, a partial adult skeleton, was discovered in Speeton, England, in 1958, but was not formally described until 2012 by Valentin Fischer and colleagues. They also recognised a partial subadult skeleton belonging to the genus from Cremlingen, Germany, and specimens from other localities in England. The genus contains the single species ''Acamptonectes densus''; the generic name means "rigid swimmer" and the specific name means "compact" or "tightly packed". The generic name refers to unusual adaptations in the body of ''Acamptonectes'' that made its trunk rigid, including tightly fitting bones in the occiput (back and lower part of the skull) and interlocking vertebral centra ("bodies" of the vertebrae), which were likely adaptations that enabled it to swim at high speeds with a tuna-like ... [...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 restricte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophthalmosaurid
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 restricte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2011 In Paleontology
Protozoa New taxa Plants Ferns and fern allies Gymnosperms Gymnosperm research *An amplified whole plant reconstruction of the Ypresian Princeton chert pine '' Pinus arnoldii'', expanding the diagnosis to include ''P. similkameenensis'' (Miller, 1973 Events January * January 1 - The United Kingdom, the Republic of Ireland and Denmark enter the European Economic Community, which later becomes the European Union. * January 15 – Vietnam War: Citing progress in peace negotiations, U.S. ...) foliage and wood plus unnamed pollens cones found in attachment to the ''P. arnoldii'' ovulate cones is published by Klymiuk, Stockey, & Rothwell. Angiosperms Nematoda Lobopods Vetulicolians Molluscs Arthropods Fishes Amphibians Newly named lepospondyls Newly named temnospondyls Newly named lissamphibians Basal reptiles Newly named captorhinids Newly named basal diapsids Newly named ichthyosaurs Lepidosauromorphs Newly named saurosphargids New ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platypterygiine
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mollesaurus
''Mollesaurus'' is an extinct genus of large ophthalmosaurine ophthalmosaurid ichthyosaur known from northwestern Patagonia of Argentina. Etymology ''Mollesaurus'' was named by Marta S. Fernández in 1999 and the type species is ''Mollesaurus periallus''. The generic name is derived from the name of the Los Molles Formation, where the holotype was collected, and ''sauros'', Greek for "lizard". The specific name is derived from ''periallos'', Greek for "before all others", in reference to the fact that it is the oldest ophthalmosaurid and one of the oldest thunnosaurs. History of study ''Mollesaurus'' is known from the holotype MOZ 2282 V, articulated partial skeleton which preserved partial skull and most of the vertebral column. It was collected in the Chacaico Sur locality from the ''Emileia giebeli'' ammonoid zone of the Los Molles Formation, Cuyo Group, dating to the early Bajocian stage of the Middle Jurassic, about 171.6-170 million years ago. ''Mollesaur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ichthyosaur
Ichthyosaurs (Ancient Greek for "fish lizard" – and ) are large extinct marine reptiles. Ichthyosaurs belong to the order known as Ichthyosauria or Ichthyopterygia ('fish flippers' – a designation introduced by Sir Richard Owen in 1842, although the term is now used more for the parent clade of the Ichthyosauria). Ichthyosaurs thrived during much of the Mesozoic era; based on fossil evidence, they first appeared around 250 million years ago ( Ma) and at least one species survived until about 90 million years ago, into the Late Cretaceous. During the Early Triassic epoch, ichthyosaurs and other ichthyosauromorphs evolved from a group of unidentified land reptiles that returned to the sea, in a development similar to how the mammalian land-dwelling ancestors of modern-day dolphins and whales returned to the sea millions of years later, which they gradually came to resemble in a case of convergent evolution. Ichthyosaurs were particularly abundant in the Late Triassic a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aegirosaurus
''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] |
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] |
Ophthalmosaurinae
Ophthalmosaurinae is an extinct subfamily of ophthalmosaurid thunnosaur ichthyosaurs from the Middle Jurassic to the late Early Cretaceous (Bajocian - Albian) of Europe, North America and South America. Currently, the oldest and the basalmost known ophthalmosaurine is ''Mollesaurus'' from the early Bajocian of Argentina. Ophthalmosaurines were characterized by a large extracondylar area of the basioccipital in the form of a thick and concave peripheral band, posterodistally deflected ulnar facet of the humerus, large ulna with concave and edgy posterior surface and ischiopubis with obturator foramen. Phylogeny Ophthalmosaurinae was named in 1887 by George H. Baur. It is a stem-based taxon defined phylogenetically for the first time by Fischer ''et al.'' (2012) as "all taxa closer to ''Ophthalmosaurus icenicus'' than to '' Platypterygius hercynicus''". The cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barremian
The Barremian is an age in the geologic timescale (or a chronostratigraphic stage) between 129.4 ± 1.5 Ma (million years ago) and 121.4 ± 1.0 Ma). It is a subdivision of the Early Cretaceous Epoch (or Lower Cretaceous Series). It is preceded by the Hauterivian and followed by the Aptian Stage.See Gradstein ''et al.'' (2004) or the online geowhen database (link below) Stratigraphic definitions The original type locality for the Barremian Stage is in the vicinity of the village of Barrême, Alpes-de-Haute-Provence, France. Henri Coquand defined the stage and named it in 1873. The base of the Barremian is determined by the first appearance of the ammonites ''Spitidiscus hugii'' and ''Spitidiscus vandeckii''. The end of the Barremian is determined by the geomagnetic reversal at the start of the M0r chronozone, which is biologically near the first appearance of the ammonite '' Paradeshayesites oglanlensis''. Regional equivalents The Barremian falls in the Gallic epoch, a su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasal Bone
The nasal bones are two small oblong bones, varying in size and form in different individuals; they are placed side by side at the middle and upper part of the face and by their junction, form the bridge of the upper one third of the nose. Each has two surfaces and four borders. Structure The two nasal bones are joined at the midline internasal suture and make up the bridge of the nose. Surfaces The ''outer surface'' is concavo-convex from above downward, convex from side to side; it is covered by the procerus and nasalis muscles, and perforated about its center by a foramen, for the transmission of a small vein. The ''inner surface'' is concave from side to side, and is traversed from above downward, by a groove for the passage of a branch of the nasociliary nerve. Articulations The nasal articulates with four bones: two of the cranium, the frontal and ethmoid, and two of the face, the opposite nasal and the maxilla. Other animals In primitive bony fish and tetrapod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
