The known remains, holotypeMCF-PVPH 77, were uncovered in layers of the Portezuelo Formation dating to the Coniacian. It consists of only a left foot, some cervical vertebrae fragments, ribs, tail chevrons and a radius.[3]
Neuquenraptor is estimated to have measured 1.8–3.5 m (5.9–11.5 ft) long and have weighed 75 kg (165 lb).[4][5] It was larger than its close relative Buitreraptor, a genus it shared some osteological and physical similarities with.[6]
Neuquenraptor might be a junior subjective synonymofUnenlagia;[7] that is, the two might represent the same genus or even species, in which case the name Unenlagia would have to be used instead of Neuquenraptor because the former name was published earlier, in 1997, and thus has priority.[8]Neuquenraptor was assigned by Novas and Pol to the Dromaeosauridae in a polytomy with several dromaeosaurid taxa.[3] Later phylogenetic analyses have not treated it as a valid genus, combining its data with that of Unenlagia into a single unit.[9][10]
Neuquenraptor enjoys a special importance because of its provenance from South America. Until the discovery of Neuquenraptor, all dromaeosaurids had been found in North America, Europe or Northern China / Mongolia, and scientists believed that dromaeosaurids only inhabited Laurasia, i.e. the Northern Hemisphere. South America however, during the Mesozoic became part of Gondwana. The find of Neuquenraptor provides some possible indication of the degree of isolation between the Northern and Southern hemispheres.[3]
The supercontinent Pangaea started to break up in the Early Jurassic, leading to the separation around 160 Ma of Laurasia in the north and Gondwana in the south. Gondwana itself was soon fragmented into West Gondwana (i.e., Africa and South America) and East Gondwana (i.e., Antarctica and Australia plus India and Madagascar). West Gondwana broke apart during the Cretaceous, as Africa and South America separated between 132 and 90 Ma. Between approximately 80 and 60 Ma, i.e. in the Late Cretaceous and early Paleocene, North America and South America were perhaps connected, at least episodically, by a land bridge, due to the eastward motion of the Caribbean plate between the two continental masses.[3]
^*Novas, F. E.; Cladera, G.; Puerta, P. (1996). "New theropods from the Late Cretaceous of Patagonia". Journal of Vertebrate Paleontology. 16: 56A. doi:10.1080/02724634.1996.10011371.
^Novas, Fernando E.; Apesteguia, Sebastian; Pol, Diego; Cambiaso, Andrea V. (1999). "Un probable troodontido (Theropoda-Coelurosauria) del Cretacico Tardio de Patagonia". Ameghiniana. 36 (4): 17.
Argentina
