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Ken Stadtman - One of the best experts on this subject based on the ideXlab platform.
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Evidence for high taxonomic and morphologic tyrannosauroid diversity in the Late Cretaceous (Late Campanian) of the American Southwest and a new short-skulled tyrannosaurid from the Kaiparowits formation of Utah
Naturwissenschaften, 2011Co-Authors: Thomas D. Carr, Thomas E. Williamson, Brooks B. Britt, Ken StadtmanAbstract:The fossil record of late Campanian tyrannosauroids of western North America has a geographic gap between the Northern Rocky Mountain Region (Montana, Alberta) and the Southwest (New Mexico, Utah). Until recently, diagnostic tyrannosauroids from the Southwest were unknown until the discovery of Bistahieversor sealeyi from the late Campanian of New Mexico. Here we describe an incomplete skull and postcranial skeleton of an unusual tyrannosaurid from the Kaiparowits Formation (Late Cretaceous) of Utah that represents a new genus and species, Teratophoneus curriei . Teratophoneus differs from other tyrannosauroids in having a short skull, as indicated by a short and steep maxilla, abrupt angle in the Postorbital Process of the jugal, laterally oriented paroccipital Processes, short basicranium, and reduced number of teeth. Teratophoneus is the sister taxon of the Daspletosaurus + Tyrannosaurus clade and it is the most basal North American tyrannosaurine. The presence of Teratophoneus suggests that dinosaur faunas were regionally endemic in the west during the upper Campanian. The divergence in skull form seen in tyrannosaurines indicates that the skull in this clade had a wide range of adaptive morphotypes.
Marcelo Mazzolli - One of the best experts on this subject based on the ideXlab platform.
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Lethal biting behaviour of pumas (Carnivora, Felidae) interpreted from fractured skull of prey Mordida fatal de puma (Carnivora, Felidae) interpretado por fraturas no crânio da presa
2020Co-Authors: Marcelo MazzolliAbstract:Biting behaviour of pumas at the moment of killing their prey is mentioned in the literature as being delivered either to the throat, nape of the neck and base of skull. Detailed anatomic descriptions of it are, however, largely absent in literature. In this article, the biting behaviour of a puma while attacking a peccary is described based on the perforations found on the skull of the prey. An observer looking at the prey-predator struggle would mistakenly conclude that the bite was meant to reach the throat region with the intent of suffocation, when in fact the bite reached and damaged the ventral and posterior region of the skull, and the spinal cord. According with the most likely hypothesis derived from matching a puma skull with that of the collared-peccary, the predator grasped it with its forepaws from behind, and bit at the upper throat region while the peccary held its head back exposing the throat region, allowing the upper canines to reach and damage the occipital bone and auditory bulla. Although there are no marks on the vertebrae, the evidence from the skull match indicate that the penetration of the upper canines into the skull allowed the top incisors to reach exactly where the atlas vertebrae and the occipital condyle connect. The lower canines held the upper part of the cranium, puncturing slightly at the Postorbital Process. The unusual behaviour of biting the skull from below may be partially due to the presence of an extended nuchal crest in collared-peccaries, which prevent predators to reach the spinal cord from above.
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Lethal biting behaviour of pumas (Carnivora, Felidae) interpreted from fractured skull of prey
Neotropical Biology and Conservation, 2013Co-Authors: Marcelo MazzolliAbstract:Biting behaviour of pumas at the moment of killing their prey is mentioned in the literature as being delivered either to the throat, nape of the neck and base of skull. Detailed anatomic descriptions of it are, however, largely absent in literature. In this article, the biting behaviour of a puma while attacking a peccary is described based on the perforations found on the skull of the prey. An observer looking at the prey-predator struggle would mistakenly conclude that the bite was meant to reach the throat region with the intent of suffocation, when in fact the bite reached and damaged the ventral and posterior region of the skull, and the spinal cord. According with the most likely hypothesis derived from matching a puma skull with that of the collared-peccary, the predator grasped it with its forepaws from behind, and bit at the upper throat region while the peccary held its head back exposing the throat region, allowing the upper canines to reach and damage the occipital bone and auditory bulla. Although there are no marks on the vertebrae, the evidence from the skull match indicate that the penetration of the upper canines into the skull allowed the top incisors to reach exactly where the atlas vertebrae and the occipital condyle connect. The lower canines held the upper part of the cranium, puncturing slightly at the Postorbital Process. The unusual behaviour of biting the skull from below may be partially due to the presence of an extended nuchal crest in collared-peccaries, which prevent predators to reach the spinal cord from above. Key words: killing behaviour, Pecari tajacu , predation, Puma concolor .
Wang Yuanqing - One of the best experts on this subject based on the ideXlab platform.
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Sinobaatar gen. nov.: First multituberculate from the Jehol Biota of Liaoning,
2020Co-Authors: Northeast China, Hu Yaoming, Wang YuanqingAbstract:A multituberculate skeleton from the Lower Cretaceous Yixian Formation at Dawangzhangzi, Lingyuan City, Liaoning Province, Northeast China, provides new morphological information for early multituberculates. The specimen is the holotype of Sinobaatar lingyuanensis gen. et sp. nov. It has a narrow skull that lacks the superorbital crest or Postorbital Process. The dental formula is 3·?·5·2/1·0·3·2. The dental morphology, especially that of cheek teeth, of S. lingyuanensis is similar to that of Eobaatar, which places it in the family Eobaataridae. The postcranial skeleton of Sino- baatar is similar to that of other multituberculates. As in Holotheria, Metatarsal V of Sinobaatar articulates only with the cuboid and has no contact with the calcaneus, which probably represents the primitive condition of multituber- culates. Nine carpals of Sinobaatar resemble those of Zhang- heotherium, except the centrale being larger than the trape- zoid. The dental features of Sinobaatar show again that eo- baatarids are obviously intermediate between Late Jurassic multituberculates and the later forms. Because eobaatarids are only known from the Early Cretaceous, the finding of Sinobaatar, therefore, supports that the age of the Jehol Bi- ota is most likely Early Cretaceous.
Yuanqing Wang - One of the best experts on this subject based on the ideXlab platform.
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Sinobaatar gen. nov.: First multituberculate from the Jehol Biota of Liaoning, Northeast China
Chinese Science Bulletin, 2002Co-Authors: Yaoming Hu, Yuanqing WangAbstract:A multituberculate skeleton from the Lower Cretaceous Yixian Formation at Dawangzhangzi, Lingyuan City, Liaoning Province, Northeast China, provides new morphological information for early multituberculates. The specimen is the holotype of Sinobaatar lingyuanensis gen. et sp. nov. It has a narrow skull that lacks the superorbital crest or Postorbital Process. The dental formula is 3.?.5.2/1.0.3.2. The dental morphology, especially that of cheek teeth, of S. lingyuanensis is similar to that of Eobaatar, which places it in the family Eobaataridae. The postcranial skeleton of Sinobaatar is similar to that of other multituberculates. As in Holotheria, Metatarsal V of Sinobaatar articulates only with the cuboid and has no contact with the calcaneus, which probably represents the primitive condition of multituberculates. Nine carpals of Sinobaatar resemble those of Zhangheotherium, except the centrale being larger than the trapezoid. The dental features of Sinobaatar show again that eobaatarids are obviously intermediate between Late Jurassic multituberculates and the later forms. Because eobaatarids are only known from the Early Cretaceous, the finding of Sinobaatar, therefore, supports that the age of the Jehol Biota is most likely Early Cretaceous.
Thomas D. Carr - One of the best experts on this subject based on the ideXlab platform.
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Evidence for high taxonomic and morphologic tyrannosauroid diversity in the Late Cretaceous (Late Campanian) of the American Southwest and a new short-skulled tyrannosaurid from the Kaiparowits formation of Utah
Naturwissenschaften, 2011Co-Authors: Thomas D. Carr, Thomas E. Williamson, Brooks B. Britt, Ken StadtmanAbstract:The fossil record of late Campanian tyrannosauroids of western North America has a geographic gap between the Northern Rocky Mountain Region (Montana, Alberta) and the Southwest (New Mexico, Utah). Until recently, diagnostic tyrannosauroids from the Southwest were unknown until the discovery of Bistahieversor sealeyi from the late Campanian of New Mexico. Here we describe an incomplete skull and postcranial skeleton of an unusual tyrannosaurid from the Kaiparowits Formation (Late Cretaceous) of Utah that represents a new genus and species, Teratophoneus curriei . Teratophoneus differs from other tyrannosauroids in having a short skull, as indicated by a short and steep maxilla, abrupt angle in the Postorbital Process of the jugal, laterally oriented paroccipital Processes, short basicranium, and reduced number of teeth. Teratophoneus is the sister taxon of the Daspletosaurus + Tyrannosaurus clade and it is the most basal North American tyrannosaurine. The presence of Teratophoneus suggests that dinosaur faunas were regionally endemic in the west during the upper Campanian. The divergence in skull form seen in tyrannosaurines indicates that the skull in this clade had a wide range of adaptive morphotypes.