Sphenodon punctatus, Tuatara skull

cults3d

This file features a 3D surface model created directly from scan data obtained from this specimen. Users can download and print it using a 3D printer or rapid prototyper, or render it within a 3D application. The files are typically quite large in size, so we do not recommend downloading them without a high-speed internet connection. This preserved adult head (YPM 9194) was collected by John Ostrom from an unknown location between the years of 1960 and 1969. It was made available to the University of Texas High-resolution X-ray CT Facility for scanning by Dr. Jacques Gauthier of Yale University, on behalf of Dr. Chris Bell of The University of Texas at Austin. Funding for image processing came from a National Science Foundation Assembling the Tree of Life grant (EF-0334961), given to Drs. Jacques Gauthier of Yale University, Maureen Kearney of the Field Museum, Mike Lee of the University of Adelaide, Jessie Maisano of The University of Texas at Austin, Tod Reeder of San Diego State University, Olivier Rieppel of the Field Museum, Jack Sites of Brigham Young University, and John Wiens of SUNY Stonybrook. Sphenodon species are also known as tuataras. They are the sole living representatives of Rhynchocephalia, which is the sister taxon to Squamata - a clade that includes lizards, snakes, and amphisbaenians. Examples include Ctenosaura pectinata, Gerrhosaurus major, Rhineura sp., and Varanus gouldii. By necessity, Sphenodon is usually used in phylogenetic analyses as the first outgroup to Squamata. However, there is a significant gap in the fossil record of rhynchocephalians from the early Cretaceous up to a subfossil, S. diversum. Extant Sphenodon has evolved significantly and this restricts its utility for determining character evolution in squamates.