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Shartegosuchidae
Shartegosuchidae is an extinct family of Late Jurassic and Early Cretaceous crocodylomorphs. The family is named after the Late Jurassic Shar Teeg Beds in southwestern Mongolia, from which most shartegosuchid remains have been found. Five genera are currently assigned to Shartegosuchidae: ''Shartegosuchus'', ''Nominosuchus'', ''Kyasuchus'', ''Adzhosuchus'', and '' Fruitachampsa''. ''Shartegosuchus'', ''Nominosuchus'', and ''Adzhosuchus'' all come from Shar Teeg, while ''Kyasuchus'' is known from the Early Cretaceous of Russia. ''Fruitachampsa'' is known from the Late Jurassic Morrison Formation of the western United States. Description Shartegosuchids are known only from cranial material, or parts of the skull and some partial skeletons. Shartegosuchids share several distinct characteristics in the skull. On the palate, the choanae (holes where the nasal cavity opens into the mouth) is placed within a deep depression of its midline. The palatal bones, located behind the choanae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shar Teeg Beds
The Ulan Malgait Formation is a Late Jurassic geologic formation in Mongolia. Dinosaur remains are among the fossils that have been recovered from the formation, although none have yet been referred to a specific genus.Weishampel et al., 2004, pp.517-607 It is best known for the Shar Teeg locality which has lent its name to Shartegosuchidae, a family of mesoeucrocodylians (relatives of crocodilians), many of which have been found there; ''Shartegosuchus'' (the family's type genus) means "Shar Teeg crocodile".Dollman et al., 2018 It is divided up into 2 subunits, the lower Shar Teg Beds and the upper Ulan Malgait Beds.Watabe, 2010 The tritylodontids '' Shartegodon, Nuurtherium'' and ''Bienotheroides'' are known from the formation.,Velazco et al., 2017 As is docodontan ''Tegotherium''. The turtles '' Annemys levensis'' and '' Annemys latiens'' and crocodylians '' Sunosuchus shartegensis'' and '' Adzhosuchus fuscus'' were also recovered from the formation.Efimov et al., 2000 Numero ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adzhosuchus
''Adzhosuchus'' is an extinct genus of crocodylomorph in the family Shartegosuchidae. Fossils have been found from southwestern Mongolia that date back to the 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 ... period.Efimov, M. B., Gubin, Y. M. and Kurzanov, S. M. (2000). New primitive crocodile (Crocodylomorpha: Shartegosuchidae) from the Jurassic of Mongolia. ''Paleontological Journal'' 34:238–241. References Late Jurassic crocodylomorphs Late Jurassic reptiles of Asia Prehistoric pseudosuchian genera {{Jurassic-reptile-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fruitachampsa
''Fruitachampsa'' is a genus of shartegosuchid crocodyliform from the Upper Jurassic Morrison Formation of Colorado. It is known from multiple specimens that show it to have been a relatively long-limbed terrestrial quadrupedal predator less than long, with a short face and a prominent pair of canine-like teeth in the lower jaw. Before it was formally described in 2011, it was also known as the "Fruita form". Its type species is ''F. callisoni''. Discovery Fossils of ''Fruitachampsa'' have been found from the Fruita Paleontological Area (FPA) in Fruita, Colorado. The deposits in the FPA belong to the Morrison Formation, which is Late Jurassic in age. The first remains of ''Fruitachampsa'' were found by paleontologists James Clark and George Callison in 1975, who discovered a diverse assemblage of microvertebrates at the FPA. More complete material of ''Fruitachampsa'' was found in 1976, 1977, and 1979. ''Fruitachampsa'' has been found alongside another more basal crocodylomorp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nominosuchus
''Nominosuchus'' is a genus of protosuchian-grade crocodylomorph. It is known from several specimens discovered in ancient lake deposits of the Tithonian-age Upper Jurassic Tsagaantsav Formation, southwestern Mongolia. The type specimen is PIN 4174/4, a partial skull. ''Nominosuchus'' was not large; its skull length is estimated at . It was similar to ''Shartegosuchus'', and is assigned to the same family (Shartegosuchidae). ''Nominosuchus'' was described in 1996 by Mikhail Efimov, and the type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ... is ''N. matutinus''. References Late Jurassic reptiles of Asia Late Jurassic crocodylomorphs Prehistoric pseudosuchian genera {{paleo-archosaur-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protosuchia
Protosuchia is a group of extinct Mesozoic crocodyliforms. They were small in size (~1 meter in length) and terrestrial. In phylogenetic terms, Protosuchia is considered an informal group because it is a grade of basal crocodyliforms, not a true clade. Classification Recent phylogenetic analyses have not supported Protosuchia as a natural group. However, two studies found a clade of Late Triassic-Early Jurassic animals:Pol D, Ji S-a, Clark JM, Chiappe LM. 2004. Basal crocodyliforms from the Lower Cretaceous Tugulu Group (Xinjiang, China), and the phylogenetic position of ''Edentosuchus''. ''Cretaceous Research'' 25: 603-622.Fiorelli LE, Calvo JO. 2007. The first "protosuchian" (Archosauria: Crocodyliformes) from the Cretaceous (Santonian) of Gondwana. ''Arquivos do Museu Nacional, Rio de Janeiro'' 65 (4): 417-459. *''Edentosuchus'' *''Hemiprotosuchus'' *''Orthosuchus'' *'' Protosuchus'' Both of these studies also found a clade more closely related to '' Hsisosuchus'' and Mesoeu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kyasuchus
''Kyasuchus'' is an extinct genus of shartegosuchid crocodylomorph. Fossils have been found from the Ilek Formation outcropping in the Kemerovo Oblast of Russia, deposited during the Aptian and Albian stages of the Early Cretaceous. The localities from which specimens of this genus have been found have also yielded many other vertebrate remains such as those of palaeonisciform fishes, turtles, various lizards, troodontids, triconodonts, the ceratopsian ''Psittacosaurus'', and the protosuchian-grade crocodylomorph ''Tagarosuchus''.Averianov, A. O., Voronkevich, A. V., Maschenko, E. N., Leshchinskiy, S. V. and Fayngertz, A. V. (2002). A sauropod foot from the Early Cretaceous of Western Siberia, Russia. ''Acta Palaeontologica Polonica'' 47(1):117–124. References External linksKyasuchusin the Paleobiology Database The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms. History The Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shartegosuchus
''Shartegosuchus'' is a genus of protosuchian-grade crocodylomorph. It is known primarily from PIN 4174/2, the partial deformed skull and jaws of a juvenile. This specimen was discovered in ancient lake deposits of the Tithonian-age Upper Jurassic Tsagaantsav Formation, southwestern Mongolia. The estimated length of the holotype skull is . This genus was similar to ''Nominosuchus'', and both are assigned to the same family (Shartegosuchidae). ''Shartegosuchus'' was described in 1988 by Mikhail Efimov, and the type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ... is ''S. asperopalatum''. References Late Jurassic reptiles of Asia Late Jurassic crocodylomorphs Prehistoric pseudosuchian genera {{paleo-archosaur-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodylomorph
Crocodylomorpha is a group of pseudosuchian archosaurs that includes the crocodilians and their extinct relatives. They were the only members of Pseudosuchia to survive the end-Triassic extinction. During Mesozoic and early Cenozoic times, crocodylomorphs were far more diverse than they are now. Triassic forms were small, lightly built, active terrestrial animals. The earliest and most primitive crocodylomorphs are represented by " sphenosuchians", a paraphyletic assemblage containing small-bodied forms with elongated limbs that walked upright, which represents the ancestral morphology of Crocodylomorpha. These forms persisted until the end of the Jurassic. During the Jurassic, Crocodylomorphs morphologically diversified into numerous niches, including into the aquatic and marine realms. Evolutionary history When their extinct species and stem group are examined, the crocodylian lineage (clade Pseudosuchia, formerly Crurotarsi) proves to have been a very diverse and adaptive ... [...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 dinosau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lacrimal Bone
The lacrimal bone is a small and fragile bone of the facial skeleton; it is roughly the size of the little fingernail. It is situated at the front part of the medial wall of the orbit. It has two surfaces and four borders. Several bony landmarks of the lacrimal bone function in the process of lacrimation or crying. Specifically, the lacrimal bone helps form the nasolacrimal canal necessary for tear translocation. A depression on the anterior inferior portion of the bone, the lacrimal fossa, houses the membranous lacrimal sac. Tears or lacrimal fluid, from the lacrimal glands, collect in this sac during excessive lacrimation. The fluid then flows through the nasolacrimal duct and into the nasopharynx. This drainage results in what is commonly referred to a runny nose during excessive crying or tear production. Injury or fracture of the lacrimal bone can result in posttraumatic obstruction of the lacrimal pathways. Structure Lateral or orbital surface The lateral or orbital surface i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadrate Bone
The quadrate bone is a skull bone in most tetrapods, including amphibians, sauropsids (reptiles, birds), and early synapsids. In most tetrapods, the quadrate bone connects to the quadratojugal and squamosal bones in the skull, and forms upper part of the jaw joint. The lower jaw articulates at the articular bone, located at the rear end of the lower jaw. The quadrate bone forms the lower jaw articulation in all classes except mammals. Evolutionarily, it is derived from the hindmost part of the primitive cartilaginous upper jaw. Function in reptiles In certain extinct reptiles, the variation and stability of the morphology of the quadrate bone has helped paleontologists in the species-level taxonomy and identification of mosasaur squamates and spinosaurine dinosaurs. In some lizards and dinosaurs, the quadrate is articulated at both ends and movable. In snakes, the quadrate bone has become elongated and very mobile, and contributes greatly to their ability to swallow very ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antorbital Fenestra
An antorbital fenestra (plural: fenestrae) is an opening in the skull that is in front of the eye sockets. This skull character is largely associated with archosauriforms, first appearing during the Triassic Period. Among extant archosaurs, birds still possess antorbital fenestrae, whereas crocodylians have lost them. The loss in crocodylians is believed to be related to the structural needs of their skulls for the bite force and feeding behaviours that they employ.Preushscoft, H., Witzel, U. 2002. Biomechanical Investigations on the Skulls of Reptiles and Mammals. Senckenbergiana Lethaea 82:207–222.Rayfield, E.J., Milner, A.C., Xuan, V.B., Young, P.G. 2007. Functional Morphology of Spinosaur "Crocodile Mimic" Dinosaurs. JVP. 27(4):892–901. In some archosaur species, the opening has closed but its location is still marked by a depression, or fossa, on the surface of the skull called the antorbital fossa. The antorbital fenestra houses a paranasal sinus that is confluent with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
