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Rugops Primus
''Rugops'' (meaning ‘wrinkle face’) is a monospecific genus of basal abelisaurid theropod dinosaur from Niger that lived during the Late Cretaceous period (Cenomanian stage, ~95 Ma) in what is now the Echkar Formation. The type and only species, ''Rugops primus'', is known only from a partial skull. It was named and described in 2004 by Paul Sereno, Jeffery Wilson and Jack Conrad. ''Rugops'' has an estimated length of 4.4–5.3 metres (14.4–17.4 ft) and weight of 410 kilograms (900 lbs). The top of its skull bears several pits which correlates with overlaying scale and the front of the snout would have had an armour-like dermis. Discovery and naming A skull pertaining to an abelisaurid was recovered during an expedition in 2000 led by Paul Sereno near In-Abangharit, Niger Republic. The specimen came from the Echkar Formation of the Tegama Group which dates to the Cenomanian stage of the Late Cretaceous period, 96 Ma. The formation has also yielded specimens pertaining to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Australia and Ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinosaurid
The Spinosauridae (or spinosaurids) are a clade or family of tetanuran theropod dinosaurs comprising ten to seventeen known genera. They came into prominence during the Cretaceous period. Spinosaurid fossils have been recovered worldwide, including Africa, Europe, South America and Asia. Their remains have generally been attributed to the Early to Mid Cretaceous. Spinosaurids were large bipedal carnivores. Their crocodilian-like skulls were long, low and narrow, bearing conical teeth with reduced or absent serrations. The tips of their upper and lower jaws fanned out into a spoon-shaped structure similar to a rosette, behind which there was a notch in the upper jaw that the expanded tip of the lower jaw fit into. The nostrils of spinosaurids were retracted to a position further back on the head than in most other theropods, and they had bony crests on their heads along the midline of their skulls. Their robust shoulders wielded stocky forelimbs, with three-fingered hands that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prefrontal Bone
The prefrontal bone is a bone separating the lacrimal and frontal bones in many tetrapod skulls. It first evolved in the sarcopterygian clade Rhipidistia, which includes lungfish and the Tetrapodomorpha. The prefrontal is found in most modern and extinct lungfish, amphibians and reptiles. The prefrontal is lost in early mammaliaforms and so is not present in modern mammals either. In dinosaurs The prefrontal bone is a very small bone near the top of the skull, which is lost in many groups of coelurosaurian theropod dinosaurs and is completely absent in their modern descendants, the birds. Conversely, a well developed prefrontal is considered to be a primitive feature in dinosaurs. The prefrontal makes contact with several other bones in the skull. The anterior part of the bone articulates with the nasal bone and the lacrimal bone. The posterior part of the bone articulates with the frontal bone and more rarely the palpebral bone The palpebral bone is a small dermal bone found ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fenestra
A fenestra (fenestration; plural fenestrae or fenestrations) is any small opening or pore, commonly used as a term in the biological sciences. It is the Latin word for "window", and is used in various fields to describe a pore in an anatomical structure. Biological morphology In morphology, fenestrae are found in cancellous bones, particularly in the skull. In anatomy, the round window and oval window are also known as the ''fenestra rotunda'' and the ''fenestra ovalis''. In microanatomy, fenestrae are found in endothelium of fenestrated capillaries, enabling the rapid exchange of molecules between the blood and surrounding tissue. The elastic layer of the tunica intima is a fenestrated membrane. In surgery, a fenestration is a new opening made in a part of the body to enable drainage or access. Plant biology and mycology In plant biology, the perforations in a perforate leaf are also described as fenestrae, and the leaf is called a fenestrate leaf. The leaf window is al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasal Bone
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 Roof
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", protec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palate
The palate () is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but in most other tetrapods, the oral and nasal cavities are not truly separated. The palate is divided into two parts, the anterior, bony hard palate and the posterior, fleshy soft palate (or velum). Structure Innervation The maxillary nerve branch of the trigeminal nerve supplies sensory innervation to the palate. Development The hard palate forms before birth. Variation If the fusion is incomplete, a cleft palate results. Function When functioning in conjunction with other parts of the mouth, the palate produces certain sounds, particularly velar, palatal, palatalized, postalveolar, alveolopalatal, and uvular consonants. History Etymology The English synonyms palate and palatum, and also the related adjective palatine (as in palatine bone), are all from the Latin ''palatum'' via Old French ''palat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holotype
A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several examples, but explicitly designated as the holotype. Under the International Code of Zoological Nomenclature (ICZN), a holotype is one of several kinds of name-bearing types. In the International Code of Nomenclature for algae, fungi, and plants (ICN) and ICZN, the definitions of types are similar in intent but not identical in terminology or underlying concept. For example, the holotype for the butterfly '' Plebejus idas longinus'' is a preserved specimen of that subspecies, held by the Museum of Comparative Zoology at Harvard University. In botany, an isotype is a duplicate of the holotype, where holotype and isotypes are often pieces from the same individual plant or samples from the same gathering. A holotype is not necessarily "typ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kaprosuchus
''Kaprosuchus'' is an extinct genus of mahajangasuchid crocodyliform. It is known from a single nearly complete skull collected from the Upper Cretaceous Echkar Formation of Niger. The name means "boar crocodile" from the Greek , ''kapros'' ("boar") and , ''soukhos'' ("crocodile") in reference to its unusually large caniniform teeth which resemble those of a boar. It has been nicknamed "BoarCroc" by Paul Sereno and Hans Larsson, who first described the genus in a monograph published in ''ZooKeys'' in 2009 along with other Saharan crocodyliformes such as ''Anatosuchus'' and ''Laganosuchus''. The type species is ''K. saharicus''. Description ''Kaprosuchus'' is known from a nearly complete skull 507 mm in length in which the lower jaw measured 603 mm long. The original description estimated the entire animal to be in length,National Geographic. November 2009. p. 140-141 although newer estimates lowered this to around 4 meters (13.1 ft). It possesses three sets of tusk- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laganosuchus
''Laganosuchus'' is an extinct genus of stomatosuchid crocodyliform. Fossils have been found from Niger and Morocco and date back to the Upper Cretaceous. Discovery The name means "pancake crocodile" from the Greek , ("pancake") and , ("crocodile") in reference to the shallow depth of the skull, which is characteristic of all stomatosuchids. It has been nicknamed "PancakeCroc" by Paul Sereno and Hans Larsson, who first described the genus in a monograph published in ''ZooKeys'' in 2009 along with other Saharan crocodyliformes such as ''Anatosuchus'' and '' Kaprosuchus''. The type species is ''L. thaumastos'' (meaning 'the astonishing pancake crocodile' from Greek θαυμαζω, ''thaumazo'' "I astonish" in reference to its unusual form) from the Cenomanian-age Echkar Formation in Niger, holotype MNN IGU13. A second species, ''L. maghrebensis'' (making a reference to the place of discovery), is known from the Kem Kem Beds in Morocco, which are also Cenomanian in age; its h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fortignathus
''Fortignathus'' is an extinct genus of dyrosaurid or peirosaurid 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, cro ... known from the Late Cretaceous Echkar Formation in Niger. It contains a Monotypic taxon, single species, ''Fortignathus felixi'', which was originally named as a species of ''Elosuchus'' in 2002. de Broin, F. de L., (2002), ''Elosuchus'', a new genus of crocodile from the Lower Cretaceous of the North of Africa: ''C. R. Palevol'', v. 1, p. 275-285. References Crocodylomorphs Fossil taxa described in 2016 {{Paleo-archosaur-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodylomorphs
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 adapti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
