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Troodontids
Troodontidae is a clade of bird-like theropod dinosaurs. During most of the 20th century, troodontid fossils were few and incomplete and they have therefore been allied, at various times, with many dinosaurian lineages. More recent fossil discoveries of complete and articulated specimens (including specimens which preserve feathers, eggs, embryos, and complete juveniles), have helped to increase understanding about this group. Anatomical studies, particularly studies of the most primitive troodontids, like ''Sinovenator'', demonstrate striking anatomical similarities with ''Archaeopteryx'' and primitive dromaeosaurids, and demonstrate that they are relatives comprising a clade called Paraves. Description Troodontids are a group of small, bird-like, gracile maniraptorans. All troodontids have unique features of the skull, such as large numbers of closely spaced teeth in the lower jaw. Troodontids have sickle-claws and raptorial hands, and some of the highest non-avian encephaliza ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jianianhualong
''Jianianhualong'' (meaning "Jianianhua dragon") is a genus of troodontid theropod dinosaur from the Early Cretaceous of China. It contains a single species, ''Jianianhualong tengi'', named in 2017 by Xu Xing and colleagues based on an articulated skeleton preserving feathers. The feathers at the middle of the tail of ''Jianianhualong'' are asymmetric, being the first record of asymmetrical feathers among the troodontids. Despite aerodynamic differences from the flight feathers of modern birds, the feathers in the tail vane of ''Jianianhualong'' could have functioned in drag reduction whilst the animal was moving. The discovery of ''Jianianhualong'' supports the notion that asymmetrical feathers appeared early in the evolutionary history of the Paraves. ''Jianianhualong'' possesses a combination of traits seen in basal as well as traits seen in derived troodontids. This is consistent with its phylogenetically intermediate position among the troodontids. This mixture of traits s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xixiasaurus
''Xixiasaurus'' () is a genus of troodontid dinosaur that lived during the Late Cretaceous Period in what is now China. The only known specimen was discovered in Xixia County, Henan Province, in central China, and became the holotype of the new genus and species ''Xixiasaurus henanensis'' in 2010. The names refer to the areas of discovery, and can be translated as "Henan Xixia lizard". The specimen consists of an almost complete skull (except for the hindmost portion), part of the lower jaw, and teeth, as well as a partial right forelimb. ''Xixiasaurus'' is estimated to have been long and to have weighed . As a troodontid, it would have been bird-like and lightly built, with grasping hands and an enlarged sickle-shaped claw on the second toe. Its skull was long, with a long, low snout that formed a tapering U-shape when seen from below. The of the forehead was dome-like in side view, which indicates it had an enlarged . It differed from other troodontids in that the front of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liaoningvenator
''Liaoningvenator'' (meaning "Liaoning hunter") is a genus of troodontid theropod dinosaur from the Early Cretaceous of China. It contains a single species, ''L. curriei'', named after paleontologist Phillip J. Currie in 2017 by Shen Cai-Zhi and colleagues from an articulated, nearly complete skeleton, one of the most complete troodontid specimens known. Shen and colleagues found indicative traits that placed ''Liaoningvenator'' within the Troodontidae. These traits included its numerous, small, and closely packed teeth, as well as the vertebrae towards the end of its tail having shallow grooves in place of neural spines on their top surfaces. Within the Troodontidae, the closest relative of ''Liaoningvenator'' was ''Eosinopteryx'', and it was also closely related to ''Anchiornis'' and ''Xiaotingia''; while these have traditionally been placed outside the Troodontidae, the phylogenetic analysis conducted by Shen and colleagues offered evidence supporting the alternative identifica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alaskan Troodontid
''Troodon'' ( ; ''Troödon'' in older sources) is a wastebasket taxon and a dubious genus of relatively small, bird-like dinosaurs known definitively from the Campanian age of the Late Cretaceous period (about 77 mya). It includes at least one species, ''Troodon formosus'', known from Montana. Discovered in October 1855, ''T. formosus'' was among the first dinosaurs found in North America, although it was thought to be a lizard until 1877. Several well-known troodontid specimens from the Dinosaur Park Formation in Alberta were once believed to be members of this genus. However, recent analyses in 2017 have found the genus to be undiagnostic and referred some of these specimens to the genus ''Stenonychosaurus'' (long believed to be synonymous with ''Troodon'') and others to the genus ''Latenivenatrix''. The genus name is Ancient Greek for "wounding tooth", referring to the teeth, which were different from those of most other theropods known at the time of their discovery. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Troodon Formosus
''Troodon'' ( ; ''Troödon'' in older sources) is a wastebasket taxon and a dubious genus of relatively small, bird-like dinosaurs known definitively from the Campanian age of the Late Cretaceous period (about 77 mya). It includes at least one species, ''Troodon formosus'', known from Montana. Discovered in October 1855, ''T. formosus'' was among the first dinosaurs found in North America, although it was thought to be a lizard until 1877. Several well-known troodontid specimens from the Dinosaur Park Formation in Alberta were once believed to be members of this genus. However, recent analyses in 2017 have found the genus to be undiagnostic and referred some of these specimens to the genus ''Stenonychosaurus'' (long believed to be synonymous with ''Troodon'') and others to the genus ''Latenivenatrix''. The genus name is Ancient Greek for "wounding tooth", referring to the teeth, which were different from those of most other theropods known at the time of their discovery. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinovenator
''Sinovenator'' (meaning "Chinese hunter") is a genus of troodontid dinosaur from China. It is from the early Cretaceous Period (geology), Period. Discovery and naming Two specimens of a troodontidae, troodontid were described in 2002 in paleontology, 2002. They are both housed in the Institute of Vertebrate Paleontology and Paleoanthropology, under the specimen numbers IVPP V 12615 and IVPP V 12583. Xu Xing (paleontologist), Xu Xing, Mark Norell, and colleagues authored the study describing them, finding the specimens to represent a new taxon, for which was chosen the binomial name, binomial ''Sinovenator changii''. The generic name was derived from the Latin word ''Sinae'', for China, and ''Venator'', or "hunter". Meemann Chang is honoured by the species name for her contributions to the study of the Jehol Fauna. As Chang is a female researcher, the epithet should have been "changae"; however, such mistakes cannot be emended according to the rules of the International Code of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jinfengopteryginae
Jinfengopteryginae is a subfamily of bird-like theropod dinosaurs known from the Cretaceous of Eurasia. This group includes relatively few genera, with members discovered in 2005 but the name erected in 2012. Like other troodontids, this group of dinosaurs resided in the Paraves potentially close to the Avialae. Description Jinfengopterygines were relatively small sized troodontids ranging from about 0.5–2 m (1.8–6.6 ft), and like other troodontids had a pair of sickle claws on each foot. These animals were feathered, as most troodontids presumably were, as shown in the type species, with typical feathering around the body an neck and especially long, vaned feathers spanning the tail. Studies on these animals' flight capabilities have determined that they would be approximately as proficient as ''Microraptor'' and ''Rahonavis''. Although most other troodontids are believed to be primarily carnivorous, specimens of this subfamily show potential omnivory, being what are p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geminiraptor
''Geminiraptor'' (meaning "twin seizer") is a genus of troodontid theropod dinosaur that lived in North America during the Early Cretaceous period. ''Geminiraptor'' was a small, ground-dwelling bipedal carnivorous paravian. The type species of ''Geminiraptor'' is ''G. suarezarum''. Discovery and naming The holotype and only known specimen of Geminiraptor is CEUM 7319, a maxilla recovered from the Lower Yellow Cat Member of the Cedar Mountain Formation, in Utah, dating from the early to late Valanginian stage (about 139 to 134 million years ago). The name refers to Drs. Marina and Celina Suarez, the twin geologists who discovered the Suarez site from which the fossil was recovered. ''G. suarezarum'' was named by Phil Senter, James I. Kirkland, John Bird and Jeff A. Bartlett in 2010. The generic name, ''Geminiraptor'', is from the Latin ''geminae'' (“twins") and ''raptor'' ("seizer"). The specific name, ''suarezarum'', uses their last name ''Suarez''. Description ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinornithoides
''Sinornithoides'' (meaning "Chinese bird form") is a genus of troodontid theropod dinosaurs containing the single species ''Sinornithoides youngi''. ''S. youngi'' lived during the Early Cretaceous ( Aptian/Albian stage, around 113 million years ago).Sereno, P.C. (2010). "Taxonomy, cranial morphology, and relationships of parrot-beaked dinosaurs (Ceratopsia: ''Psittacosaurus'')." ''New Perspectives on Horned Dinosaurs''. Bloomington: Indiana, 21-58. It measured approximately one meter long (3.3 ft). It lived in Inner Mongolia, China, and probably ate invertebrates and other small prey. They lived in what is now Mongolia, which was part of Laurasia. Discovery In 1988, a Chinese-Canadian expedition discovered the remains of a small theropod near Huamuxiao, in the Ordos Basin of Inner Mongolia. ''Sinornithoides youngi'', the type species, was named and described in 1993/1994 by Dale Russell and Dong Zhiming based on this fossil specimen from the Lower Cretaceous Ejinhoro Fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mei Long
''Mei'' (from Chinese 寐 mèi ''Sleepy'') is a genus of duck-sized troodontid dinosaur first unearthed by paleontologists from the Yixian Formation in Liaoning, China in 2004. ''Mei'' lived during the Early Cretaceous period. The binomial name of its only species, ''Mei long'' (Chinese 寐 mèi and 龍 lóng), means ''sleeping dragon''. Description ''Mei'' is a troodontid, a group of small, bird-like, gracile maniraptorans. All troodontids have many unique features of the skull, such as closely spaced teeth in the lower jaw, and large numbers of teeth. Troodontids have sickle-claws and raptorial hands, and some of the highest non-avian encephalization quotients, meaning they were behaviourally advanced and had keen senses. The type fossil is a young juvenile about long, complete and exceptionally well preserved in three-dimensional detail, with the snout nestled beneath one of the forelimbs and the legs neatly folded beneath the body, similar to the roosting position of m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Talos (dinosaur)
''Talos'' is an extinct genus of carnivorous bird-like theropod dinosaur, an advanced troodontid which lived during the late Cretaceous period (late Campanian, about 76 Ma) in the geographic area that is now Utah, United States. Discovery ''Talos'' is known only from the holotype specimen UMNH VP 19479, a partial postcranial skeleton of a subadult individual including the hindlimbs, pelvis, vertebral fragments, chevrons and the left ulna. It was discovered and collected in 2008 by M. J. Knell during the Kaiparowits Basin Project, initiated by the University of Utah in 2000, from the Kaiparowits Formation within the Grand Staircase–Escalante National Monument. It was first named by Lindsay E. Zanno, David J. Varricchio, Patrick M. O'Connor, Alan L. Titus, and Michael J. Knell in 2011 and the type species is ''Talos sampsoni''. The generic name comes from Talos, a giant bronze automaton in Greek mythology and is intended to be a pun on the English word ''talon''. The spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theropoda
Theropoda (; ), whose members are known as theropods, is a dinosaur clade that is characterized by hollow bones and three toes and claws on each limb. Theropods are generally classed as a group of saurischian dinosaurs. They were ancestrally carnivorous, although a number of theropod groups evolved to become herbivores and omnivores. Theropods first appeared during the Carnian age of the late Triassic Period (geology), period 231.4 million years ago (Year#SI prefix multipliers, Ma) and included all the large terrestrial carnivores from the Early Jurassic until at least the close of the Cretaceous, about 66 Ma. In the Jurassic, birds evolved from small specialized coelurosaurian theropods, and are today represented by about 10,500 living species. Biology Diet and teeth Theropods exhibit a wide range of diets, from insectivores to herbivores and carnivores. Strict carnivory has always been considered the ancestral diet for theropods as a group, and a wider variety of di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
