Novas Fernando E, Pol Diego
CONICET, Museo Argentino de Ciencias Naturales Bernardino Rivadavia, Av. Angel Gallardo 470, Buenos Aires 1405, Argentina.
Nature. 2005 Feb 24;433(7028):858-61. doi: 10.1038/nature03285.
Most of what is known about the evolution of deinonychosaurs (that is, the group of theropods most closely related to birds) is based on discoveries from North America and Asia. Except for Unenlagia comahuensis and some fragmentary remains from northern Africa, no other evidence was available on deinonychosaurian diversity in Gondwana. Here we report a new, Late Cretaceous member of the clade, Neuquenraptor argentinus gen. et sp. nov., representing uncontroversial evidence of a deinonychosaurian theropod in the Southern Hemisphere. The new discovery demonstrates that Cretaceous theropod faunas from the southern continents shared greater similarity with those of the northern landmasses than previously thought. Available evidence suggests that deinonychosaurians were probably distributed worldwide at least by the beginning of the Cretaceous period. The phylogenetic position of the new deinonychosaur, as well as other Patagonian coelurosaurian theropods, is compatible with a vicariance model of diversification for some groups of Gondwanan and Laurasian dinosaurs.
目前已知的关于恐爪龙类（即与鸟类关系最为密切的兽脚亚目类群）演化的大部分信息都基于在北美洲和亚洲的发现。除了科马约猎龙以及来自北非的一些零散化石外，关于冈瓦纳大陆恐爪龙类多样性并无其他证据。在此，我们报告了该分支的一个新的晚白垩世成员——阿根廷内乌肯盗龙（Neuquenraptor argentinus），属名及种名均为新拟，它代表了南半球存在恐爪龙类兽脚亚目的无可争议的证据。这一新发现表明，南半球大陆白垩纪兽脚亚目动物群与北半球大陆的动物群之间的相似性比之前认为的更高。现有证据表明，至少在白垩纪早期，恐爪龙类可能已分布于全球。新发现的恐爪龙以及其他巴塔哥尼亚虚骨龙类兽脚亚目的系统发育位置，与冈瓦纳和劳亚大陆某些恐龙类群的隔离分化模型相符。
