A new hadrosauroid dinosaur, Shuangmiaosaurus gilmorei gen. et sp. nov., is described based on a complete left maxilla with articulated premaxilla and lacrimal fragments, and a complete left dentary from the mid-Creta...A new hadrosauroid dinosaur, Shuangmiaosaurus gilmorei gen. et sp. nov., is described based on a complete left maxilla with articulated premaxilla and lacrimal fragments, and a complete left dentary from the mid-Cretaceous Sunjiawan Formation of Beipiao, Liaoning, northeastern China. Cladistic analysis shows that Shuangmiaosaurus is a basal hadrosauroid, and comprises the sister taxon to Hadrosauridae. In both Shuangmiaosaurus and Hadrosauridae, the maxilla-jugal suture is butt-jointed, rather than finger-in-recess articulation as in other basal hadrosauroids. However, Shuangmiaosaurus does not possess such hadrosaurid synapomorphies as the diamond-shaped maxillary crowns with reduced primary ridges and reduced marginal denticles.展开更多
A new hadrosaurid dinosaur, Nanningosaurus dashiensis gen. et sp. nov., is described based on an incomplete skeleton from the Late Cretaceous red beds of the Nalong Basin, Guangxi, southern China. Diagnostic features ...A new hadrosaurid dinosaur, Nanningosaurus dashiensis gen. et sp. nov., is described based on an incomplete skeleton from the Late Cretaceous red beds of the Nalong Basin, Guangxi, southern China. Diagnostic features for the new taxon include the presence of a tall and sharply peaked dorsal process of the maxilla with reduced process of the jugal and a distinct lacrimal facet, gracile humerus with low, rounded deltopectoral crest, mandibular condyle of the quadrate transversly broad with reduced paraquadrate notch, dentary tooth with sinuous median carina and subsidiary ridge, relatively few tooth positions, ischial shaft straight along most of its distance, but to curve dorsally and expand at the distal end before the ischial foot begins. Phylogenetic analysis suggests that Nanningosaurus dashiensis is a basal member of Lambeosaurinae.展开更多
Four main dinosaur-bearing sites have been investigated in latest Cretaceous deposits from the Amur/Heilongjiang Region ： Jiayin and Wulaga in China （ Yuliangze Formation）, Blagoveschensk and Kundur in Russia （Udu...Four main dinosaur-bearing sites have been investigated in latest Cretaceous deposits from the Amur/Heilongjiang Region ： Jiayin and Wulaga in China （ Yuliangze Formation）, Blagoveschensk and Kundur in Russia （Udurchukan Formation）. More than 90% of the bones discovered in these localities belong to hollow-crested lambeosaurine hadrosaurids： Charonosaurus fiayinensis at Jiayin, Amurosaurus riabinini at Blagoveschensk, Olorotitan arharensis at Kundur, and Sahaliyania elunchunorum at Wulaga. Flat-headed hadrosaurine hadrosaurids are much less numerous, but appear well diversified as well： Kerberosaurus manakini at Blagoveschensk, Wulagasaurus dongi at Wulaga, and a new genus at Kundur. Theropods are represented by shed teeth and isolated bones; isolated scutes and teeth discovered at Kundur are tentatively attributed to nodosaurids. Palynological studies suggest that these sites are probably synchronous with the Lancian＇ vertebrate localities of western North America, which represent the youngest dinosaur faunas in this area. However, the latest Cretaceous dinosaur assemblages are completely different in the Amur/Heilongjiang region （lambeosaurines abundant, ceratopsids absent） and in western North America （ceratopsids abundant, lainbeosaurines extremely rare or absent）. This probably reflects some kind of geographical barrier between both areas by Maastrichtian time rather than strong differences in palaeoecological conditions.展开更多
文摘A new hadrosauroid dinosaur, Shuangmiaosaurus gilmorei gen. et sp. nov., is described based on a complete left maxilla with articulated premaxilla and lacrimal fragments, and a complete left dentary from the mid-Cretaceous Sunjiawan Formation of Beipiao, Liaoning, northeastern China. Cladistic analysis shows that Shuangmiaosaurus is a basal hadrosauroid, and comprises the sister taxon to Hadrosauridae. In both Shuangmiaosaurus and Hadrosauridae, the maxilla-jugal suture is butt-jointed, rather than finger-in-recess articulation as in other basal hadrosauroids. However, Shuangmiaosaurus does not possess such hadrosaurid synapomorphies as the diamond-shaped maxillary crowns with reduced primary ridges and reduced marginal denticles.
基金We thank Bucky Gates （Utah Museum of Natural History） for reviewing the manuscript. Thanks also give to Zhang Guobin from IVPP, Zhou Shichu from NHMG for preparing the specimens. This work was supported by funds both from the Science and Technology Department of Guangxi and State Administration of Cultural Heritage. The research work was also supported by fund from the National Science Foundation of China and Chinese Academy of Sciences to Xu Xing.
文摘A new hadrosaurid dinosaur, Nanningosaurus dashiensis gen. et sp. nov., is described based on an incomplete skeleton from the Late Cretaceous red beds of the Nalong Basin, Guangxi, southern China. Diagnostic features for the new taxon include the presence of a tall and sharply peaked dorsal process of the maxilla with reduced process of the jugal and a distinct lacrimal facet, gracile humerus with low, rounded deltopectoral crest, mandibular condyle of the quadrate transversly broad with reduced paraquadrate notch, dentary tooth with sinuous median carina and subsidiary ridge, relatively few tooth positions, ischial shaft straight along most of its distance, but to curve dorsally and expand at the distal end before the ischial foot begins. Phylogenetic analysis suggests that Nanningosaurus dashiensis is a basal member of Lambeosaurinae.
基金the Belgian State,Federal Scientific Policy,S&T bilateral co-operation project BL/36/C22-R12National Geographic Society project 6970-01+4 种基金Jurassic FoundationFWOFNRSNSFC Project 30220130698supported by the Fonds pour la Formationàla Recherche dans l'Industrie et dans l'Agriculture
文摘Four main dinosaur-bearing sites have been investigated in latest Cretaceous deposits from the Amur/Heilongjiang Region ： Jiayin and Wulaga in China （ Yuliangze Formation）, Blagoveschensk and Kundur in Russia （Udurchukan Formation）. More than 90% of the bones discovered in these localities belong to hollow-crested lambeosaurine hadrosaurids： Charonosaurus fiayinensis at Jiayin, Amurosaurus riabinini at Blagoveschensk, Olorotitan arharensis at Kundur, and Sahaliyania elunchunorum at Wulaga. Flat-headed hadrosaurine hadrosaurids are much less numerous, but appear well diversified as well： Kerberosaurus manakini at Blagoveschensk, Wulagasaurus dongi at Wulaga, and a new genus at Kundur. Theropods are represented by shed teeth and isolated bones; isolated scutes and teeth discovered at Kundur are tentatively attributed to nodosaurids. Palynological studies suggest that these sites are probably synchronous with the Lancian＇ vertebrate localities of western North America, which represent the youngest dinosaur faunas in this area. However, the latest Cretaceous dinosaur assemblages are completely different in the Amur/Heilongjiang region （lambeosaurines abundant, ceratopsids absent） and in western North America （ceratopsids abundant, lainbeosaurines extremely rare or absent）. This probably reflects some kind of geographical barrier between both areas by Maastrichtian time rather than strong differences in palaeoecological conditions.
