A juvenile specimen of a new coelurosaur (Dinosauria: Theropoda) from the Middle–Late Jurassic Shishugou Formation of Xinjiang, People's Republic of China

We describe the anatomy of a new coelurosaurian theropod <i>Aorun zhaoi</i> gen. et sp. nov., from the Middle–Late Jurassic of Xinjiang, China. Histological analysis of the holotype and only known specimen shows that the new taxon is represented by the skeleton of a juvenile individual aged no more than one year. A phylogenetic analysis of theropod relationships places <i>Aorun</i> as a basal member of the Coelurosauria. Although the sole use of a sub-adult ontogenetic exemplar is potentially problematic for phylogenetic reconstruction, we show that the phylogenetic position of <i>Aorun</i> as a member of Coelurosauria is robust to the exclusion of characters known to change during theropod ontogeny. <i>Aorun</i> is the seventh theropod taxon, and temporally oldest coelurosaur, known from the Shishugou Formation, which has one of the most taxonomically diverse Jurassic coelurosaurian theropod faunas in the world.http://zoobank.org/urn:lsid:zoobank.org:pub:5CC73577-9EB3-47AB-9983-1677B278EFFD

我们记述了来自中国新疆中晚侏罗世的虚骨龙类兽脚类（coelurosaurian theropod）新属新种赵氏奥龙（Aorun zhaoi）的解剖学特征。对正模标本及唯一已知标本的组织学分析显示，该新类群的标本来自一具年龄不超过1岁的幼年个体。针对兽脚类亲缘关系开展的系统发育分析表明，奥龙（Aorun）属于虚骨龙类的基干成员。尽管仅采用亚成体个体作为发育学样本可能对系统发育重建造成潜在局限，但本研究证实，在剔除已知会随兽脚类个体发育发生改变的特征后，奥龙作为虚骨龙类成员的系统发育位置依然保持稳健。奥龙是石树沟组（Shishugou Formation）中已发现的第七种兽脚类类群，同时也是该组中时代最为古老的虚骨龙类；而石树沟组拥有全球分类多样性最高的侏罗纪虚骨龙类兽脚类动物群之一。http://zoobank.org/urn:lsid:zoobank.org:pub:5CC73577-9EB3-47AB-9983-1677B278EFFD