A New Saurolophine Dinosaur from the Latest Cretaceous of Far Eastern Russia

<div><h3>Background</h3><p>Four main dinosaur sites have been investigated in latest Cretaceous deposits from the Amur/Heilongjiang Region: Jiayin and Wulaga in China (Yuliangze Formation), Blagoveschensk and Kundur in Russia (Udurchukan Formation). More than 90% of the bones discovered in these localities belong to hollow-crested lambeosaurine saurolophids, but flat-headed saurolophines are also represented: <em>Kerberosaurus manakini</em> at Blagoveschensk and <em>Wulagasaurus dongi</em> at Wulaga.</p> <h3>Methodology/Principal Findings</h3><p>Herein we describe a new saurolophine dinosaur, <em>Kundurosaurus nagornyi</em> gen. et sp. nov., from the Udurchukan Formation (Maastrichtian) of Kundur, represented by disarticulated cranial and postcranial material. This new taxon is diagnosed by four autapomorphies.</p> <h3>Conclusions/Significance</h3><p>A phylogenetic analysis of saurolophines indicates that <em>Kundurosaurus nagornyi</em> is nested within a rather robust clade including <em>Edmontosaurus</em> spp., <em>Saurolophus</em> spp., and <em>Prosaurolophus maximus</em>, possibly as a sister-taxon for <em>Kerberosaurus manakini</em> also from the Udurchukan Formation of Far Eastern Russia. The high diversity and mosaic distribution of Maastrichtian hadrosaurid faunas in the Amur-Heilongjiang region are the result of a complex palaeogeographical history and imply that many independent hadrosaurid lineages dispersed without any problem between western America and eastern Asia at the end of the Cretaceous.</p>