Zhejiang Museum of Natural History, Hangzhou, Zhejiang, 310014, People's Republic of China.
Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, 100044, People's Republic of China.
Sci Rep. 2018 Feb 27;8(1):3711. doi: 10.1038/s41598-018-21924-7.
The tail club knob is a highly specialized structure thought to characterize a subgroup of the ankylosaurine ankylosaurians, and the oldest documented tail club knob in the fossil record occurred in the Campanian ankylosaurine Pinacosaurus. Here we report a new ankylosaurid Jinyunpelta sinensis, gen. et sp. nov., from the Albian-Cenomanian Liangtoutang Formation, Jinyun County, Zhejiang, China. This is the first definitive and the best preserved ankylosaurid dinosaur ever found in southern China. Jinyunpelta possesses unique cranial features differs from other ankylosaurs including two paranasal apertures level with and posterior to the external naris, a triangular fossa on the anterodorsal edge of the maxilla, an antorbital fossa in the junction between the maxilla, lacrimal and jugal, and an anterior process of the prearticular that lies ventral to the splenial. Our phylogenetic analysis suggests Jinyunpelta as the most basal ankylosaurine dinosaur. Jinyunpelta has a tail club with interlocking caudal vertebrae and a well-developed tail club knob, it represents the oldest and the most basal ankylosaurian known to have a well-developed tail club knob. The new discovery thus demonstrates that a large and highly modified tail club evolved at the base of the ankylosaurine ankylosaurs at least about 100 million years ago.
尾锤棒是一种高度特化的结构，被认为是甲龙类恐龙的一个亚群的特征，而化石记录中最早出现的尾锤棒出现在坎潘阶的甲龙类恐龙钉状龙。在这里，我们报道了一种来自中国浙江缙云县白垩纪阿尔比阶至赛诺曼阶梁驮滩组的新的甲龙类恐龙——中华缙云甲龙，属名和种名都为新命名。这是中国南方首次发现的最确定和保存最完好的甲龙类恐龙。中华缙云甲龙具有独特的头骨特征，与其他甲龙类恐龙不同，包括两个副鼻窦与外鼻孔平齐且位于其后、上颌骨前背缘有一个三角形的凹坑、上颌骨、泪骨和颧骨交界处有眶前窝、以及前关节突位于方骨腹侧。我们的系统发育分析表明，中华缙云甲龙是最基础的甲龙类恐龙。中华缙云甲龙有一个带有连锁尾椎的尾锤棒和一个发育良好的尾锤棒锤，它代表了已知最古老和最基础的甲龙类恐龙，具有发达的尾锤棒锤。这一新的发现表明，一个大型且高度特化的尾巴在甲龙类恐龙的基部至少在 1 亿年前就已经进化出来了。
