title: The Quadratojugal of Eryops studied by computed tomography and the morphological variability of foramina and canals in the quadratojugal of basal tetrapods.
abstract: With respect to its large size and abundance, Eryops is an important representative of Permo-Carboniferous basal tetrapods and one of the best-known large temnospondyl amphibians of this period. This taxon forms a significant component of the Early Permian tetrapod fauna of Texas and New Mexico and here we describe a new record of skull remains, the first one from Brushy Creek (30 km northeast of Seymour) in Texas (Petrolia Formation, Wichita Group; Lower Permian - lower Artinskian). Our material, found in 2015, consists of a left nasal, a jaw fragment (premaxilla or maxilla), left quadratojugal fragments, and a partial left mandible. We used computed tomography methods (micro-CT) for imaging both internal and external structures, for the first time, for Eryops. The quadratojugal presented here is exceptional compared to all known basal tetrapods in having four different internal foramina. CT data show that these foramina are interconnected by canals within the bone. This indicates that the morphology of the foramina and the course of the canals in the quadratojugal of basal tetrapods are more variable than hitherto thought. Anat Rec, 299:1073-1079, 2016. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Ecology, Comenius University in Bratislava, Faculty of Natural Sciences, Mlynská Dolina, Ilkovičova 6, Bratislava, 842 15, Slovakia.|Museum Für Naturkunde - Leibniz-Institut Für Evolutions- Und Biodiversitätsforschung an Der Humboldt-Universität Zu Berlin, Invalidenstr. 43, Berlin, 10115, Germany.
authors.forename: Andrej
authors.initials: A
authors.lastname: Čerňanský
authors.affiliation: Museum Für Naturkunde - Leibniz-Institut Für Evolutions- Und Biodiversitätsforschung an Der Humboldt-Universität Zu Berlin, Invalidenstr. 43, Berlin, 10115, Germany.|Department of Ecology and Evolutionary Biology, Brown University, G-B204, Providence, Rhode Island, 02912.
authors.forename: Florian
authors.initials: F
authors.lastname: Witzmann
authors.affiliation: Department of Ecology, Comenius University in Bratislava, Faculty of Natural Sciences, Mlynská Dolina, Ilkovičova 6, Bratislava, 842 15, Slovakia.
authors.forename: Jozef
authors.initials: J
authors.lastname: Klembara
authors.affiliation: Leitung der Sektion Mammalogie - Head of the Mammology Section, Zoologische Staatssammlung München, Münchhausenstraße 21, 81247, München, Germany.
authors.forename: Anneke H
authors.initials: AH
authors.lastname: van Heteren
mesh_terms: D000663:Amphibians / Q000033:anatomy & histology*; D000818:Animals; D005580:Fossils; D008334:Mandible / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D008437:Maxilla / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D012886:Skull / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Lower Permian; North America; anatomy; paraquadrate foramen; temnospondyl