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Harpacochampsa
''Harpacochampsa'' is a poorly known Early Miocene crocodilian from the Bullock Creek lagerstätte of the Northern Territory, Australia. The current specimen consists of a partial skull and fragments of a long, slender snout reminiscent of that of a false gharial, demonstrating that it was a piscivore in life. It was originally tentatively placed within a group of Australian crocodilians now known as the Mekosuchinae, although this has been frequently disputed, with other authors instead suggesting it may have been a more basal crocodyloid or a type of gavialid. History and naming ''Harpacochampsa'' was named on the basis of several bones, primarily of the skull, discovered at the Bullock Creek fossil site in the Northern Territory of Australia. The type description lists four specimens, the holotype being formed by the right side of the back of the skull, preserving both the infratemporal fenestra and the supratemporal fenestra. Additional fossils include the tip of the snout ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harpacochampsa Baru
''Harpacochampsa'' is a poorly known Early Miocene crocodilian from the Bullock Creek lagerstätte of the Northern Territory, Australia. The current specimen consists of a partial skull and fragments of a long, slender snout reminiscent of that of a false gharial, demonstrating that it was a piscivore in life. It was originally tentatively placed within a group of Australian crocodilians now known as the Mekosuchinae, although this has been frequently disputed, with other authors instead suggesting it may have been a more basal crocodyloid or a type of gavialid. History and naming ''Harpacochampsa'' was named on the basis of several bones, primarily of the skull, discovered at the Bullock Creek fossil site in the Northern Territory of Australia. The type description lists four specimens, the holotype being formed by the right side of the back of the skull, preserving both the infratemporal fenestra and the supratemporal fenestra. Additional fossils include the tip of the snout ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mekosuchinae
Mekosuchinae is an extinct clade of crocodilians from the Cenozoic of Australasia. They first appear in the fossil record in the Eocene in Australia, and survived until the arrival of humans: in the Pleistocene in Australia and within the Holocene in the Pacific islands of Fiji, New Caledonia and Vanuatu. Mekosuchine crocodiles are a diverse group. One of the last species, ''Mekosuchus inexpectatus'' from Holocene New Caledonia, may have been arboreal. The early Miocene species '' Harpacochampsa camfieldensis'' may have resembled a false gharial. Another mekosuchine fossil, currently undescribed, has been found in Miocene deposits from New Zealand. One genus, ''Mekosuchus'', managed to spread to the islands of the Pacific; it is believed to have island-hopped across the Coral Sea, moving first to a now submerged island known as Greater Chesterfield Island, then New Caledonia and onwards. In the Pleistocene, ''Quinkana'' was one of the top terrestrial predators of the Australian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gavialidae
Gavialidae is a family (biology), family of large semiaquatic crocodilians with elongated, narrow snouts. Gavialidae consists of two extant taxon, living species, the gharial (''Gavialis gangeticus'') and the false gharial (''Tomistoma schlegelii''), both occurring in Asia. Many extinct members are known from a broader range, including the recently extinct ''Hanyusuchus''. Gavialids are generally regarded as lacking the jaw strength to capture the large mammalian prey favoured by crocodiles and alligators of similar size so their thin snout is best used to catch fish, however the false gharial has been found to have a Generalist and specialist species, generalist diet with mature adults preying upon larger vertebrates, such as Ungulate, ungulates. Taxonomy The family Gavialidae was proposed by Arthur Adams (zoologist), Arthur Adams in 1854 for reptiles with a very long and slender muzzle, webbed feet and nearly equal teeth. It is currently recognized as a crown group, meaning that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
False Gharial
The false gharial (''Tomistoma schlegelii''), also known by the names Malayan gharial, Sunda gharial and tomistoma is a freshwater crocodilian of the family Gavialidae native to Peninsular Malaysia, Borneo, Sumatra and Java. It is listed as Vulnerable on the IUCN Red List, as the global population is estimated at around 2,500 to 10,000 mature individuals. The specific name ''schlegelii'' honors Hermann Schlegel. Taxonomy The scientific name ''Crocodilus (Gavialis) schlegelii'' was proposed by Salomon Müller in 1838 who described a specimen collected in Borneo. In 1846, he proposed to use the name ''Tomistoma schlegelii'', if it needs to be placed in a distinct genus. The genus ''Tomistoma'' potentially also contains several extinct species like ''T. cairense'', ''T. lusitanicum'', ''T. taiwanicus'', and ''T. coppensi''. However, these species may need to be reclassified to different genera as are paraphyletic. The false gharial's snout broadens considerably towards the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gavialis Lewisi
''Gavialis'' is a genus of crocodylians that includes the living gharial ''Gavialis gangeticus'' and one known extinct species, '' Gavialis bengawanicus.'' ''G. gangeticus'' comes from the Indian Subcontinent, while ''G. bengawanicus'' is known from Java. ''Gavialis'' likely first appeared in the Indian Subcontinent in the Pliocene and dispersed into the Malay Archipelago through a path called the Siva–Malayan route in the Quaternary. Remains attributed to ''Gavialis'' have also been found on Sulawesi and Woodlark Island east of the Wallace Line, suggesting a prehistoric lineage of ''Gavialis'' was able to traverse marine environments and reach places possibly as far as western Oceania. The genus ''Gavialis'' was reevaluated in 2018 based on specimens in the Natural History Museum, London that were collected in the Sivalik Hills. The author concluded that ''G. gangeticus'' and '' G. bengawanicus'' are the only two species in the genus ''Gavialis'', with '' G. hysudricus'' as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gharial
The gharial (''Gavialis gangeticus''), also known as gavial or fish-eating crocodile, is a crocodilian in the family Gavialidae and among the longest of all living crocodilians. Mature females are long, and males . Adult males have a distinct boss at the end of the snout, which resembles an earthenware pot known as a ''ghara'', hence the name "gharial". The gharial is well adapted to catching fish because of its long, narrow snout and 110 sharp, interlocking teeth. The gharial probably evolved in the northern Indian subcontinent. Fossil gharial remains were excavated in Pliocene deposits in the Sivalik Hills and the Narmada River valley. It currently inhabits rivers in the plains of the northern part of the Indian subcontinent. It is the most thoroughly aquatic crocodilian, and leaves the water only for basking and building nests on moist sandbanks. Adults mate at the end of the cold season. Females congregate in spring to dig nests, in which they lay 20–95 eggs. They guard t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Premaxillae
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 f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasal Bones
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] |
Skull Table
The skull roof, or the roofing bones of the skull, are a set of bones covering the brain, eyes and nostrils in bony fishes and all land-living vertebrates. The bones are derived from dermal bone and are part of the dermatocranium. In comparative anatomy the term is used on the full dermatocranium. Romer, A.S. & T.S. Parsons. 1977. ''The Vertebrate Body.'' 5th ed. Saunders, Philadelphia. (6th ed. 1985) In general anatomy, the roofing bones may refer specifically to the bones that form above and alongside the brain and neurocranium (i.e., excluding the marginal upper jaw bones such as the maxilla and premaxilla), and in human anatomy, the skull roof often refers specifically to the skullcap. Origin Early armoured fish did not have a skull in the common understanding of the word, but had an endocranium that was partially open above, topped by dermal bones forming armour. The dermal bones gradually evolved into a fixed unit overlaying the endocranium like a heavy "lid", protectin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Miocene
The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene Epoch made up of two stages: the Aquitanian and Burdigalian stages. The sub-epoch lasted from 23.03 ± 0.05 Ma to 15.97 ± 0.05 Ma (million years ago). It was preceded by the Oligocene epoch. As the climate started to get cooler, the landscape started to change. New mammals evolved to replace the extinct animals of the Oligocene epoch. The first members of the hyena and weasel family started to evolve to replace the extinct ''Hyaenodon'', entelodonts and bear-dogs. The chalicotheres survived the Oligocene epoch. A new genus of entelodont called ''Daeodon'' evolved in order to adapt to the new habitats and hunt the new prey animals of the Early Miocene epoch; it quickly became the top predator of North America. But it became extinct due to competition from '' Amphicyon'', a newcomer from Eurasia. ''Amphicyon'' bested ''Daeodon'' because the bear-dog Amphicyonidae is an extinct family of terrestr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supratemporal Fenestrae
The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, these two parts are the neurocranium and the viscerocranium (facial skeleton) that includes the mandible as its largest bone. The skull forms the anterior-most portion of the skeleton and is a product of cephalisation—housing the brain, and several sensory structures such as the eyes, ears, nose, and mouth. In humans these sensory structures are part of the facial skeleton. Functions of the skull include protection of the brain, fixing the distance between the eyes to allow stereoscopic vision, and fixing the position of the ears to enable sound localisation of the direction and distance of sounds. In some animals, such as horned ungulates (mammals with hooves), the skull also has a defensive function by providing the mount (on the frontal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
