24 January 2017
The Neuquensaurus australis phylogeny is complex and has an interesting history (feel free to disagree if phylogenetic history is not exciting to you!). Originally described as a member of the genus Titanosaurus by Lydekker in 1893 (Titanosaurus australis), Neuquensaurus was bounced around the titanosaur family tree. Lydekker's 1893 description of the dinosaur does not appear anywhere online or I would, as I often do, recommend reading this to learn more about the holotype remains. However, this is not the end of the Neuquensaurus tail an there are many other papers that reappraise the materials and their placement. One such paper (also not available online unfortunately) is the result of Friedrich von Heune's inspections of the Neuquensaurus material. In 1929 von Heune placed a number of contested elements of Neuquensaurus into a new genus (Laplatasaurus). Von Heune noted that many of the elements of Neuquensaurus were not entirely dissimilar from Titanosaurus and so the name held until 1986 when Jaime Eduardo Powell named the new genus Neuquensaurus based on the material being less similar to Titanosaurus than even Laplatasaurus was. Powell's assertions based on his dissertation's redescriptions (titled Revisión del titanosáuridos de América del Sur)were not accepted until 1992, when the book Los Dinosaurios y Su Entorno Biotico: Actas del Segundo Curso de Paleontologia in Cuenca was published. Powell was not renaming Titanosaurus australis at this time though, as it had been reassigned to Saltasaurus, a medium sized North and Central American sauropod, in 1990 by John Stanton McIntosh; meaning he was renaming Saltasaurus australis. One interested more in the phylogeny of Neuquensaurus should check out this more modern article by Salgado, et al. that describes a new specimen of the dinosaur discovered in Northern Patagonia. More specific descriptions of systems of the dinosaur have also been researched, studied, and published as well. These include the appendicular skeleton (Otero 2010), hindlimb attributes (Otero 2008), and vertebral diversity (Zurriaguz 2016).