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Cerrejonisuchus
''Cerrejonisuchus'' is an extinct genus of dyrosaurid crocodylomorph. It is known from a complete skull and mandible from the Cerrejón Formation in northeastern Colombia, which is Paleocene in age. Specimens belonging to ''Cerrejonisuchus'' and to several other dyrosaurids have been found from the Cerrejón open-pit coal mine in La Guajira. The length of the rostrum is only 54-59% of the total length of the skull, making the snout of ''Cerrejonisuchus'' the shortest of all dyrosaurids. Description At an estimated length of to , ''Cerrejonisuchus'' was small for a dyrosaur. This size estimate is based on the dorsal skull lengths of specimens UF/IGM 29 and UF/IGM 31. ''Cerrejonisuchus'' has the shortest body length of any known dyrosaur, much smaller than that of the longest dyrosaur, ''Phosphatosaurus gavialoides'', which was to in length. Currently the only known specimens of ''Cerrejonisuchus'' are UF/IGM 29 (the type specimen), UF/IGM 30, UF/IGM 31, and UF/IGM 32. Of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyrosauridae
Dyrosauridae is a family of extinct neosuchian crocodyliforms that lived from the Late Cretaceous (Maastrichtian) to the Eocene. Dyrosaurid fossils are globally distributed, having been found in Africa, Asia, Europe, North America and South America. Over a dozen species are currently known, varying greatly in overall size and cranial shape. A majority were aquatic, some terrestrial and others fully marine (see locomotion below), with species inhabiting both freshwater and marine environments. Ocean-dwelling dyrosaurids were among the few marine reptiles to survive the Cretaceous–Paleogene extinction event. The dyrosaurids were a group of mostly marine, long jawed, crocodile-like quadrupeds up to long. The largest dyrosaurid was probably ''Phosphatosaurus'' estimated at in length. Based on bone tissue evidence, it has been hypothesized that they were slow-growing near-shore marine animals with interlocking closed jaws, able to swim as well as walk on land. External nostrils at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerrejón Formation
The Cerrejón Formation is a geologic formation in Colombia dating back to the Middle-Late Paleocene. It is found in the El Cerrejón sub-basin of the Cesar-Ranchería Basin of La Guajira and Cesar. The formation consists of bituminous coal fields that are an important economic resource. Coal from the Cerrejón Formation is mined extensively from the Cerrejón open-pit coal mine, one of the largest in the world. The formation also bears fossils that are the earliest record of Neotropical rainforests.Wing et al., 2009 Definition The formation was first named Septarias Formation and in 1958 renamed to Cerrejón Formation by Thomas van der Hammen, probably based on an earlier report by Notestein.Rodríguez & Londoño, 2002, p.163 Geology The Cerrejón Formation, with an assigned total thickness of , is subdivided into lower, middle, and upper groups based on the thickness and distribution of coal beds. On average the coal beds are thick, and range from to in thickness. The t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peligran
The Peligran ( es, Peligrense) age is a period of geologic time (62.5–59.0 Ma) within the Paleocene epoch of the Paleogene, used more specifically with South American land mammal ages (SALMA). It follows the Tiupampan and precedes the Riochican age. Etymology The age is named after the paleontological site Punta Peligro Punta is an Afro-indigenous dance and cultural music originating in the Caribbean Island of Saint Vincent And The Grenadines by the Garifuna people before being exiled from the island. Which is also known as Yurumei. It has African and Arawa ... in Argentina. Formations Fossils References Bibliography ;Peñas Coloradas Formation * * ;Bogotá Formation * * * ;Cerrejón Formation * * * * * * * * * * * * * ;Chota Formation * * ;Guaduas Formation * ;Salamanca Formation * * * * * ;Santa Lucía Formation * * * * * * * * * {{SALMA Paleocene South America Paleogene Argentina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Itaboraian
The Itaboraian ( pt, Itaboraiense) age is a period within the Early Eocene geologic time (53.0–50.0 Mya (unit), Ma) epoch of the Paleogene, used more specifically with South American land mammal ages (SALMA). It follows the Riochican and precedes the Casamayoran age. Etymology This age is named after the Itaboraí Formation in the Itaboraí Basin in Itaboraí, a Rio de Janeiro metropolitan area, Greater Rio municipality in the state of Rio de Janeiro (state), Rio de Janeiro in Brazil not very far away from Niterói. Formations Fossils Correlations References Bibliography ;Itaboraí Formation * * * * * * ;Bogotá Formation * * * ;Cerrejón Formation * * * * * * * * * * * * * ;Chota Formation * * ;Las Flores Formation * * * ;Koluel Kaike Formation * ;Maíz Gordo Formation * ;Mogollón Formation * * ;Muñani Formation * ;Peñas Coloradas Formation * * ;Río Loro Formation * {{SALMA Itaboraian, Paleocene Sout ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anatomical Terms Of Location
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabularies for subdisciplines of anatom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nostril
A nostril (or naris , plural ''nares'' ) is either of the two orifices of the nose. They enable the entry and exit of air and other gasses through the nasal cavities. In birds and mammals, they contain branched bones or cartilages called turbinates, whose function is to warm air on inhalation and remove moisture on exhalation. Fish do not breathe through noses, but they do have two (but cyclostomes have merged into one) small holes used for smelling, which can also be referred to as nostrils. In humans, the nasal cycle is the normal ultradian cycle of each nostril's blood vessels becoming engorged in swelling, then shrinking. The nostrils are separated by the septum. The septum can sometimes be deviated, causing one nostril to appear larger than the other. With extreme damage to the septum and columella, the two nostrils are no longer separated and form a single larger external opening. Like other tetrapods, humans have two external nostrils (anterior nares) and two additi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbit (anatomy)
In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. "Orbit" can refer to the bony socket, or it can also be used to imply the contents. In the adult human, the volume of the orbit is , of which the eye occupies . The orbital contents comprise the eye, the orbital and retrobulbar fascia, extraocular muscles, cranial nerves II, III, IV, V, and VI, blood vessels, fat, the lacrimal gland with its sac and duct, the eyelids, medial and lateral palpebral ligaments, cheek ligaments, the suspensory ligament, septum, ciliary ganglion and short ciliary nerves. Structure The orbits are conical or four-sided pyramidal cavities, which open into the midline of the face and point back into the head. Each consists of a base, an apex and four walls."eye, human."Encyclopædia Britannica from Encyclopædia Britannica 2006 Ultimate Reference Suite DVD 2009 Openings There are two important foramina, or windows, two important fissu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homodont
In anatomy, a heterodont (from Greek, meaning 'different teeth') is an animal which possesses more than a single tooth morphology. In vertebrates, heterodont pertains to animals where teeth are differentiated into different forms. For example, members of the Synapsida generally possess incisors, canines ("eyeteeth"), premolars, and molars. The presence of heterodont dentition is evidence of some degree of feeding and or hunting specialization in a species. In contrast, homodont or isodont dentition refers to a set of teeth that possess the same tooth morphology. In invertebrates, the term heterodont refers to a condition where teeth of differing sizes occur in the hinge plate, a part of the Bivalvia Bivalvia (), in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs that have laterally compressed bodies enclosed by a shell consisting of two hinged parts. As a group, biva .... References See also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maxilla
The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxillary bones are fused at the intermaxillary suture, forming the anterior nasal spine. This is similar to the mandible (lower jaw), which is also a fusion of two mandibular bones at the mandibular symphysis. The mandible is the movable part of the jaw. Structure In humans, the maxilla consists of: * The body of the maxilla * Four processes ** the zygomatic process ** the frontal process of maxilla ** the alveolar process ** the palatine process * three surfaces – anterior, posterior, medial * the Infraorbital foramen * the maxillary sinus * the incisive foramen Articulations Each maxilla articulates with nine bones: * two of the cranium: the frontal and ethmoid * seven of the face: the nasal, zygomatic, lacrimal, inferior n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleocene
The Paleocene, ( ) or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name is a combination of the Ancient Greek ''palaiós'' meaning "old" and the Eocene Epoch (which succeeds the Paleocene), translating to "the old part of the Eocene". The epoch is bracketed by two major events in Earth's history. The K–Pg extinction event, brought on by Chicxulub impact, an asteroid impact and possibly volcanism, marked the beginning of the Paleocene and killed off 75% of living species, most famously the non-avian dinosaurs. The end of the epoch was marked by the Paleocene–Eocene Thermal Maximum (PETM), which was a major climatic event wherein about 2,500–4,500 gigatons of carbon were released into the atmosphere and ocean systems, causing a spike in global temperatures and ocean acidification. In the Pal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Premaxilla
The premaxilla (or praemaxilla) is one of a pair of small cranial bones at the very tip of the upper jaw of many animals, usually, but not always, bearing teeth. In humans, they are fused with the maxilla. The "premaxilla" of therian mammal has been usually termed as the incisive bone. Other terms used for this structure include premaxillary bone or ''os premaxillare'', intermaxillary bone or ''os intermaxillare'', and Goethe's bone. Human anatomy In human anatomy, the premaxilla is referred to as the incisive bone (') and is the part of the maxilla which bears the incisor teeth, and encompasses the anterior nasal spine and alar region. In the nasal cavity, the premaxillary element projects higher than the maxillary element behind. The palatal portion of the premaxilla is a bony plate with a generally transverse orientation. The incisive foramen is bound anteriorly and laterally by the premaxilla and posteriorly by the palatine process of the maxilla. It is formed from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyrosaurus
''Dyrosaurus'' is a genus of extinct crocodylomorph that lived during the early Eocene. The name ''Dyrosaurus'' comes from () the Greek for lizard or reptile, and Dyr for Djebel Dyr (mountain) close to where the type species was discovered. It was a large reptile with an estimated body length of . Species Although the family Dyrosauridae is quite diverse and contains a variety of species, the genus ''Dyrosaurus'' has only two described species: ''D. phosphaticus'' and ''D. maghribensis''. ''D. phosphaticus'' was first discovered in Algeria and Tunisia whereas ''D. maghribensis'' has only been found in Morocco. ''D. maghribensis'' differs from ''D. phosphaticus'' by several synapomorphies, most notably: a smooth dorsal margin of the parietal and widely opened choanae, interfenestral bar wide and strongly T-shaped instead of moderately T-shaped. In ''D. maghribensis'' the lateral and medial dorsal osteoderms are not sutured and have no serrated margin. The anterolateral margin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
