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Ignotosaurus
''Ignotosaurus'' is an extinct genus of silesaurid dinosauriform known from the Late Triassic (Carnian) Cancha de Bochas Member of the Ischigualasto Formation in the Ischigualasto-Villa Unión Basin in northwestern Argentina.Martínez et al., 2013 It was therefore contemporary with early dinosaurs such as ''Herrerasaurus,'' and lived in the same place. Etymology The name, meaning 'unknown lizard' from the Latin 'ignotus' 'unknown' and the Greek '' 'lizard', is quite apt as there is only one specimen known and this specimen is only known from the right ilium. This ilium is approximately long, but it is difficult to say accurately how large ''Ignotosaurus'' was. Description The ilium is slender, and its blade has an extremely thin central portion (only thick), hence the specific name 'fragilis'. It has the saddle-shaped lateral profile of most silesaurids, and is longer than it is deep. The acetabulum has a back wall created by a ventral flange and this closes a socket ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silesaurid
Silesauridae is an extinct family of Triassic dinosauriforms. It is most commonly considered to be a clade of non-dinosaur dinosauriforms, and the sister group of dinosaurs. Some studies have instead suggested that most or all silesaurids comprised an early diverging clade or a paraphyletic grade within ornithischian dinosaurs. Silesaurids have a consistent general body plan, with a fairly long neck and legs and possibly quadrupedal habits, but most silesaurids are heavily fragmentary nonetheless. Furthermore, they occupied a variety of ecological niches, with early silesaurids (such as '' Lewisuchus'') being carnivorous and later taxa (such as ''Kwanasaurus'') having adaptations for specialized herbivory. As indicated by the contents of referred coprolites, ''Silesaurus'' may have been insectivorous, feeding selectively on small beetles and other arthropods. Classification Silesauridae is typically considered the sister group to Dinosauria. The group was named in 2010 by Max ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ischigualasto Formation
The Ischigualasto Formation is a Late Triassic geological formation in the Ischigualasto-Villa Unión Basin of southwestern La Rioja Province, Argentina, La Rioja Province and northeastern San Juan Province, Argentina, San Juan Province in northwestern Argentina. The formation dates to the late Carnian and early Norian stages of the Late Triassic (around 231.7 to 225 Ma), according to radiometric dating of ash beds. The Ischigualasto Formation is part of the Agua de la Peña Group, overlying the Los Rastros Formation and overlain by the Los Colorados Formation. The formation is typically subdivided into four Member (geology), members, from old to young; La Peña, Cancha de Bochas, Valle de la Luna and Quebrada de la Sal. The sandstones, mudstones, conglomerate (geology), conglomerates and tuffs of the formation were deposited in an fluvial (river-dominated) floodplain depositional environment, environment, characterized by cool temperatures and strongly seasonal rainfall. The form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carnian
The Carnian (less commonly, Karnian) is the lowermost stage (stratigraphy), stage of the Upper Triassic series (stratigraphy), Series (or earliest age (geology), age of the Late Triassic Epoch (reference date), Epoch). It lasted from 237 to 227.3 megaannum, million years ago (Ma). The Carnian is preceded by the Ladinian and is followed by the Norian. Its boundaries are not characterized by major extinctions or biotic turnovers, but a climatic event (known as the Carnian pluvial episode characterized by substantial rainfall) occurred during the Carnian and seems to be associated with important extinctions or biotic radiations. Another extinction occurred at the Carnian-Norian boundary, ending the Carnian age. Stratigraphic definitions The Carnian was named in 1869 by Johann August Georg Edmund Mojsisovics von Mojsvar, Mojsisovics. It is unclear if it was named after the Carnic Alps or after the Austrian region of Carinthia (state), Carinthia (''Kärnten'' in German) or after th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Femur
The femur (; : femurs or femora ), or thigh bone is the only long bone, bone in the thigh — the region of the lower limb between the hip and the knee. In many quadrupeds, four-legged animals the femur is the upper bone of the hindleg. The Femoral head, top of the femur fits into a socket in the pelvis called the hip joint, and the bottom of the femur connects to the shinbone (tibia) and kneecap (patella) to form the knee. In humans the femur is the largest and thickest bone in the body. Structure The femur is the only bone in the upper Human leg, leg. The two femurs converge Anatomical terms of location, medially toward the knees, where they articulate with the Anatomical terms of location, proximal ends of the tibiae. The angle at which the femora converge is an important factor in determining the femoral-tibial angle. In females, thicker pelvic bones cause the femora to converge more than in males. In the condition genu valgum, ''genu valgum'' (knock knee), the femurs conve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Vertebrate Paleontology
The ''Journal of Vertebrate Paleontology'' is a bimonthly peer-reviewed scientific journal that was established in 1980 by Jiri Zidek (University of Oklahoma). It covers all aspects of vertebrate paleontology, including vertebrate origins, evolution, functional morphology, taxonomy, biostratigraphy, paleoecology, paleobiogeography, and paleoanthropology. The journal is published by Taylor & Francis on behalf of the Society of Vertebrate Paleontology. According to ''Journal Citation Reports'', the journal has a 2017 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ... of 2.190. References External links * Paleontology journals Academic journals established in 1980 Quarterly journals English-language journals Taylor & Francis academic journals {{Oklahoma- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cynodont
Cynodontia () is a clade of eutheriodont therapsids that first appeared in the Late Permian (approximately 260 Megaannum, mya), and extensively diversified after the Permian–Triassic extinction event. Mammals are cynodonts, as are their extinct ancestors and close relatives (Mammaliaformes), having evolved from advanced probainognathian cynodonts during the Late Triassic. Non-mammalian cynodonts occupied a variety of ecological niches, both as carnivores and as herbivores. Following the emergence of mammals, most other cynodont lines went extinct, with the last known non-mammaliaform cynodont group, the Tritylodontidae, having its youngest records in the Early Cretaceous. Description Early cynodonts have many of the skeletal characteristics of mammals. The teeth were fully differentiated and the braincase bulged at the back of the head. Outside of some Crown group, crown-group mammals (notably the therians), all cynodonts probably laid eggs. The temporal fenestrae#Fenestra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhynchosaur
Rhynchosaurs are a group of extinct herbivorous Triassic archosauromorph reptiles, belonging to the order Rhynchosauria. Members of the group are distinguished by their triangular skulls and elongated, beak like premaxillary bones. Rhynchosaurs first appeared in the Early Triassic, reaching their broadest abundance and a global distribution during the Carnian stage of the Late Triassic. Description Rhynchosaurs were herbivores, and at times abundant (in some fossil localities accounting for 40 to 60% of specimens found), with stocky bodies and a powerful beak. Early primitive forms, like '' Mesosuchus'' and '' Howesia'', were generally small, typically lizard-like in build, and had skulls rather similar to the early diapsid ''Youngina'', except for the beak and a few other features. Later and more advanced genera grew to up to two meters in length. The skull in these forms were short, broad, and triangular, becoming much wider than long in the most advanced forms like '' Hype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herbivore
A herbivore is an animal anatomically and physiologically evolved to feed on plants, especially upon vascular tissues such as foliage, fruits or seeds, as the main component of its diet. These more broadly also encompass animals that eat non-vascular autotrophs such as mosses, algae and lichens, but do not include those feeding on decomposed plant matters (i.e. detritivores) or macrofungi (i.e. fungivores). As a result of their plant-based diet, herbivorous animals typically have mouth structures ( jaws or mouthparts) well adapted to mechanically break down plant materials, and their digestive systems have special enzymes (e.g. amylase and cellulase) to digest polysaccharides. Grazing herbivores such as horses and cattles have wide flat- crowned teeth that are better adapted for grinding grass, tree bark and other tougher lignin-containing materials, and many of them evolved rumination or cecotropic behaviors to better extract nutrients from plants. A larg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drainage Basin
A drainage basin is an area of land in which all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, the drainage divide, made up of a succession of elevated features, such as ridges and hills. A basin may consist of smaller basins that merge at river confluences, forming a hierarchical pattern. Other terms for a drainage basin are catchment area, catchment basin, drainage area, river basin, water basin, and impluvium. In North America, they are commonly called a watershed, though in other English-speaking places, " watershed" is used only in its original sense, that of the drainage divide line. A drainage basin's boundaries are determined by watershed delineation, a common task in environmental engineering and science. In a closed drainage basin, or endorheic basin, rather than flowing to the ocean, water converges toward the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossilisation
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Though the fossil record is incomplete, numerous studies have demonstrated that there is enough information available to give a good understanding of the pattern of diversification of life on Earth. In addition, the record can predict and fill gaps such as the discovery of ''Tiktaalik'' in the arctic of Canada. Paleontology includes the study of fossils: their age, method of formation, and evolutionary significance. Specimens are sometimes considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years to 4.1 billion years old. Early edition, published online before print. The ob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
