1 A NEW LATE CRETACEOUS IGUANOMORPH FROM NORTH AMERICA AND THE 2 ORIGIN OF NEW WORLD PLEURODONTA (SQUAMATA, IGUANIA) 3 4 David G. DeMar, Jr.1, Jack L. Conrad†, Jason J. Head2, David J. Varricchio3, and Gregory P. 5 Wilson 1 6 7 1Department of Biology and Burke Museum of Natural History and Culture, University of 8 Washington, Seattle, WA 98195, USA 9 2Department of Zoology and University Museum of Zoology, University of Cambridge, CB2 10 3EJ, Cambridge, UK 11 3Department of Earth Sciences, Montana State University, Bozeman, MT 59717, USA 12 Author for correspondence: 13 David G. DeMar, Jr. 14
[email protected] 15 Subject areas: 16 Palaeontology, phylogenetics, evolution 17 Keywords: Iguanomorpha, Pleurodonta, Cretaceous, Palaeogene, palaeobiogeography, 18 palaeoecology 19 20 †Deceased. Last places of employment: Department of Anatomy, NYIT College of Osteopathic Medicine, Old Westbury, NY, 11568, USA and Department of Vertebrate Paleontology, American Museum of Natural History, New York, NY, 10024, USA. Date of passing: July 21, 2016. 1 21 Abstract 22 Iguanomorpha (stem + crown Iguania) is a diverse squamate clade with members that 23 predominate many modern American lizard ecosystems. However, the temporal and 24 palaeobiogeographic origins of its constituent crown clades (e.g., Pleurodonta [basilisks, iguanas, 25 and their relatives]) are poorly constrained, mainly due to a meager Mesozoic-age fossil record. 26 Here, we report on two nearly complete skeletons from the Late Cretaceous (Campanian) of 27 North America that represent a new and relatively large-bodied and possibly herbivorous 28 iguanomorph that inhabited a semi-arid environment. The new taxon exhibits a mosaic of 29 anatomical features traditionally used in diagnosing Iguania and non-iguanian squamates (i.e., 30 Scleroglossa) (e.g., parietal foramen at the frontoparietal suture, astragalocalcaneal notch in the 31 tibia, respectively).