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Caninemys Skull
''Caninemys'' is an extinct genus of large freshwater side-necked turtle, belonging to the family Podocnemididae. Its fossils have been found in Brazil and Colombia, in rocks dating back from the middle to late Miocene. Discovery and naming The type specimen of ''Caninemys'', a well preserved skull (DNPM-MCT 1496-R), was found in 1962 in Acre State, Brazil by Llewellyn Ivor Price. Originally mentioned by Lapparent de Broin (1993) alongside several shell fragments similar to ''Stupendemys'', it was concluded that the data was not sufficient enough to refer the skull to the massive podocnemid, especially in the light of other similarly sized turtle remains from Miocene South America. In 2009 Meylan, Gaffney and De Almeida Campos described ''Caninemys'' on the basis of the skull alone, not including the shell fragments mentioned by de Broin due to the possibility of a chimeric combination. They do however consider it very probable that LACM 141498, a lower jaw, belongs to the same t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caninemys Skull
''Caninemys'' is an extinct genus of large freshwater side-necked turtle, belonging to the family Podocnemididae. Its fossils have been found in Brazil and Colombia, in rocks dating back from the middle to late Miocene. Discovery and naming The type specimen of ''Caninemys'', a well preserved skull (DNPM-MCT 1496-R), was found in 1962 in Acre State, Brazil by Llewellyn Ivor Price. Originally mentioned by Lapparent de Broin (1993) alongside several shell fragments similar to ''Stupendemys'', it was concluded that the data was not sufficient enough to refer the skull to the massive podocnemid, especially in the light of other similarly sized turtle remains from Miocene South America. In 2009 Meylan, Gaffney and De Almeida Campos described ''Caninemys'' on the basis of the skull alone, not including the shell fragments mentioned by de Broin due to the possibility of a chimeric combination. They do however consider it very probable that LACM 141498, a lower jaw, belongs to the same t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Podocnemis Expansa
The Arrau turtle (''Podocnemis expansa''), also known as the South American river turtle, giant South American turtle, giant Amazon River turtle, Arrau sideneck turtle, Amazon River turtle or simply the Arrau, is the largest of the side-neck turtles (Pleurodira) and the largest freshwater turtle in Latin America. The species primarily feeds on plant material and typically nests in large groups on beaches. Due to hunting of adults, collecting of their eggs, pollution, habitat loss, and dams, the Arrau turtle is seriously threatened. Range and habitat Arrau turtles are found in the Amazon, Orinoco and Essequibo basins in Brazil, Bolivia, Peru, Ecuador, Colombia, Venezuela and Guyana. On occasion, typically after floods, individuals turn up in Trinidad. They are found in deep rivers, ponds, freshwater lagoons and flooded forest in white-, black- and clear-water. Appearance Arrau turtles can reach up to in weight and the carapace length is up to . Most individuals are conside ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bairdemys
''Bairdemys'' is an extinct genus of side-necked turtles in the family Podocnemididae. The genus existed from the Late Oligocene to Late Miocene and its fossils have been found in South Carolina, Puerto Rico, Panama and Venezuela. The genus was described in 2002 by Gaffney & Wood and the type species is ''B. hartsteini''. Description The first species in the genus described was ''B. venezuelensis'' as '' Podocnemis venezuelensis'' by Wood and Díaz de Gamero in 1971.Gaffney et al., 2008 Species * ''B. hartsteini'' * ''B. healeyorum'' * ''B. sanchezi'' * ''B. thalassica'' * ''B. venezuelensis'' * ''B. winklerae'' Phylogeny ''Bairdemys'' was placed phylogenetically by Ferreira et al. in 2015.Ferreira et al., 2015, p.10 Distribution Fossils of ''Bairdemys'' have been found in:''Bairdemys'' at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Palate
The secondary palate is an anatomical structure that divides the nasal cavity from the oral cavity in many vertebrates. In human embryology, it refers to that portion of the hard palate that is formed by the growth of the two palatine shelves medially and their mutual fusion in the midline. It forms the majority of the adult palate and meets the primary palate at the incisive foramen. Clinical significance Secondary palate development begins in the sixth week of pregnancy and can lead to cleft palate when development goes awry. There are three major mechanisms known to cause this failure: #Growth retardation — Palatal shelves do not grow enough to meet each other. #Mechanical obstruction — Improper mouth size, or abnormal anatomical structures in the embryonic mouth prevent fully grown shelves from meeting each other. #Midline epithelial dysfunction (MED)Dudas et al. (2007): Palatal fusion – Where do the midline cells go? A review on cleft palate, a major hum ... [...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] |
Alligator Snapping Turtle
The alligator snapping turtle (''Macrochelys temminckii'') is a large species of turtle in the family Chelydridae. The species is native to freshwater habitats in the United States. ''M. temminckii'' is one of the heaviest freshwater turtles in the world. It is the largest freshwater species of turtle in North America. It is often associated with, but not closely related to, the common snapping turtle, which is in the genus ''Chelydra''. The specific epithet ''temminckii'' is in honor of Dutch zoologist Coenraad Jacob Temminck. Taxonomy Although it was once believed that only one extant species exists in the genus '' Macrochelys'', recent studies have shown that there are two species, the other being the Suwannee snapping turtle (''M. suwanniensis'') of the Suwannee River. A third species, the Apalachicola snapping turtle (''M. apalachicolae''), has been proposed, but is generally not recognized. The alligator snapping turtle is given its common name because of its imme ... [...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] |
Parietal Bone
The parietal bones () are two bones in the Human skull, skull which, when joined at a fibrous joint, form the sides and roof of the Human skull, cranium. In humans, each bone is roughly quadrilateral in form, and has two surfaces, four borders, and four angles. It is named from the Latin ''paries'' (''-ietis''), wall. Surfaces External The external surface [Fig. 1] is convex, smooth, and marked near the center by an eminence, the parietal eminence (''tuber parietale''), which indicates the point where ossification commenced. Crossing the middle of the bone in an arched direction are two curved lines, the superior and inferior temporal lines; the former gives attachment to the temporal fascia, and the latter indicates the upper limit of the muscular origin of the temporal muscle. Above these lines the bone is covered by a tough layer of fibrous tissue – the epicranial aponeurosis; below them it forms part of the temporal fossa, and affords attachment to the temporal muscle. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frontal Bone
The frontal bone is a bone in the human skull. The bone consists of two portions.''Gray's Anatomy'' (1918) These are the vertically oriented squamous part, and the horizontally oriented orbital part, making up the bony part of the forehead, part of the bony orbital cavity holding the eye, and part of the bony part of the nose respectively. The name comes from the Latin word ''frons'' (meaning " forehead"). Structure of the frontal bone The frontal bone is made up of two main parts. These are the squamous part, and the orbital part. The squamous part marks the vertical, flat, and also the biggest part, and the main region of the forehead. The orbital part is the horizontal and second biggest region of the frontal bone. It enters into the formation of the roofs of the orbital and nasal cavities. Sometimes a third part is included as the nasal part of the frontal bone, and sometimes this is included with the squamous part. The nasal part is between the brow ridges, and ends in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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