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The Early Evolution of Rhynchosaurs Butler, Richard; Montefeltro, Felipe; Ezcurra, Martin University of Birmingham The early evolution of Rhynchosaurs Butler, Richard; Montefeltro, Felipe; Ezcurra, Martin DOI: 10.3389/fevo.2015.00142 License: Creative Commons: Attribution (CC BY) Document Version Publisher's PDF, also known as Version of record Citation for published version (Harvard): Butler, R, Montefeltro, F & Ezcurra, M 2016, 'The early evolution of Rhynchosaurs', Frontiers in Ecology and Evolution. https://doi.org/10.3389/fevo.2015.00142 Link to publication on Research at Birmingham portal Publisher Rights Statement: Frontiers is fully compliant with open access mandates, by publishing its articles under the Creative Commons Attribution licence (CC-BY). Funder mandates such as those by the Wellcome Trust (UK), National Institutes of Health (USA) and the Australian Research Council (Australia) are fully compatible with publishing in Frontiers. Authors retain copyright of their work and can deposit their publication in any repository. The work can be freely shared and adapted provided that appropriate credit is given and any changes specified. General rights Unless a licence is specified above, all rights (including copyright and moral rights) in this document are retained by the authors and/or the copyright holders. The express permission of the copyright holder must be obtained for any use of this material other than for purposes permitted by law. •Users may freely distribute the URL that is used to identify this publication. •Users may download and/or print one copy of the publication from the University of Birmingham research portal for the purpose of private study or non-commercial research. •User may use extracts from the document in line with the concept of ‘fair dealing’ under the Copyright, Designs and Patents Act 1988 (?) •Users may not further distribute the material nor use it for the purposes of commercial gain. Where a licence is displayed above, please note the terms and conditions of the licence govern your use of this document. When citing, please reference the published version. Take down policy While the University of Birmingham exercises care and attention in making items available there are rare occasions when an item has been uploaded in error or has been deemed to be commercially or otherwise sensitive. If you believe that this is the case for this document, please contact [email protected] providing details and we will remove access to the work immediately and investigate. Download date: 04. Oct. 2021 ORIGINAL RESEARCH published: 11 January 2016 doi: 10.3389/fevo.2015.00142 The Early Evolution of Rhynchosaurs Martín D. Ezcurra 1, 2*, Felipe Montefeltro 2, 3 and Richard J. Butler 2 1 Sección Paleontología de Vertebrados, Museo Argentino de Ciencias Naturales “Bernardino Rivadavia,” Buenos Aires, Argentina, 2 School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, UK, 3 Departamento de Biologia e Zootecnia, FEIS, Universidade Estadual Paulista, Ilha Solteira, Brazil The rhynchosaurian archosauromorphs are an important and diverse group of fossil tetrapods that first appeared during the Early Triassic and probably became extinct during the early Late Triassic (early Norian). Here, the early evolution of rhynchosaurs during the Early and early Middle Triassic (Induan-Anisian: 252.2-242 Mya) is reviewed based on new anatomical observations and their implications for the taxonomy, phylogenetic relationships and macroevolutionary history of the group. A quantitative phylogenetic analysis recovered a paraphyletic genus Rhynchosaurus, with “Rhynchosaurus” brodiei more closely related to hyperodapedontines than to Rhynchosaurus articeps. Therefore, a new genus is erected, resulting in the new combination Langeronyx brodiei. A body size analysis found two independent increases in size in the evolutionary history of rhynchosaurs, one among stenaulorhynchines and the other in the hyperodapedontine lineage. Maximum likelihood fitting of phenotypic evolution models to body size data Edited by: Michel Laurin, found ambiguous results, with body size evolution potentially interpreted as fitting either Muséum National d’Histoire Naturelle, a non-directional Brownian motion model or a stasis model. A Dispersal-Extinction- France Cladogenesis analysis reconstructed the areas that are now South Africa and Europe Reviewed by: Sean P. Modesto, as the ancestral areas of Rhynchosauria and Rhynchosauridae, respectively. The Cape Breton University, Canada reconstruction of dispersal events between geographic areas that are broadly separated Fernando Abdala, paleolatitudinally implies that barriers to the dispersal of rhynchosaurs from either side of University of the Witwatersrand, Johannesburg, South Africa the paleo-Equator during the Middle Triassic were either absent or permeable. Juan Carlos Cisneros, Universidade Federal do Piauí, Brazil Keywords: Permo-Triassic, Diapsida, Archosauromorpha, body size, phylogeny, paleobiogeography *Correspondence: Martín D. Ezcurra [email protected] INTRODUCTION ∼ Specialty section: The Permo-Triassic mass extinction occurred 252 million years ago, and produced a dramatic This article was submitted to change in the composition of floral and faunal communities (Raup and Sepkoski, 1982; Erwin, Paleontology, 1994; Looy et al., 2001; Benton and Twitchett, 2003; Fröbisch, 2013; Benton and Newell, 2014; a section of the journal Smith and Botha-Brink, 2014). In the case of vertebrates, numerous new lineages first appeared or Frontiers in Ecology and Evolution Received: 20 August 2015 Institutional Abbreviations: AM, Albany Museum, Grahamstown, South Africa; BRSUG, University of Bristol, School of Accepted: 30 November 2015 Earth Sciences, Bristol, UK; EXEMS, Royal Albert Memorial Museum, Exeter, UK; FZB, Fundação Zoobotânica do Rio Published: 11 January 2016 Grande do Sul, Porto Alegre, Brazil; GPIT, Paläontologische Sammlung der Universität Tübingen, Tübingen, Germany; ISI, Indian Statistical Institute, Kolkata, India; MACN-Pv, Museo Argentino de Ciencias Naturales “Bernardino Rivadavia,” Citation: Paleontología de Vertebrados, Buenos Aires, Argentina; NHMUK PV, Natural History Museum, Palaeontology Vertebrates, Ezcurra MD, Montefeltro F and London, UK; PIMUZ, Paläontologisches Institut und Museum der Universität Zürich, Zurich, Switzerland; PVSJ, Museo Butler RJ (2016) The Early Evolution of de Ciencias Naturales, Universidad de San Juan, San Juan, Argentina; SAM-PK, Iziko South African Museum, Cape Rhynchosaurs. Town, South Africa; SIDMM, Sidmouth Museum, Sidmouth, UK; SHYMS, Shropshire Museums, Ludlow, UK; UFRGS, Front. Ecol. Evol. 3:142. Instituto de Geociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; WARMS, Warwickshire Museum, doi: 10.3389/fevo.2015.00142 Warwick, UK. Frontiers in Ecology and Evolution | www.frontiersin.org 1 January 2016 | Volume 3 | Article 142 Ezcurra et al. Early Rhynchosaurs diversified in the aftermath of this extinction. Many of these Fodonyx spenceri based on new, first-hand observations of lineages replaced clades that flourished during the Paleozoic but specimens. We added three characters from previously published vanished or were decimated at the end-Permian mass extinction phylogenetic analyses relevant to the basal relationships of event (e.g., pareiasaurs, non-mammalian synapsids, such as Rhynchosauria (Dilkes, 1998; Ezcurra et al., 2014, 2015) and gorgonopsians and anomodonts). Among the new Triassic we modified the formulation of two characters from the clades are the first representatives of several modern vertebrate original character list of Butler et al. (2015: characters 63 groups, including teleosts, lissamphibians, eucynodonts, stem- and 84; see Supplementary Material). We also expanded the testudinatans, lepidosauromorphs, crocodylomorphs, and stem- taxonomic sampling of the analysis by adding the oldest known avialans, including the first non-avian dinosaurs (Bonaparte, rhynchosaur, Noteosuchus colletti (Watson, 1912; Carroll, 1976; 1982; Benton, 1983a; Colbert, 1984; Gaffney, 1986; Arratia, 2001; Dilkes, 1998; Ezcurra et al., 2014). Scoring of taxa was based Bonaparte et al., 2003; Evans, 2003; Marjanovic and Laurin, 2008; primarily on first-hand examination of specimens, with the Nesbitt, 2011; Jones et al., 2013; Ezcurra et al., 2014; Schoch and exception of Isalorhynchus genovefae, which was scored using Sues, 2015). Langer et al. (2000a) and Whatley (2005). The Triassic also witnessed the evolution of numerous The final matrix (15 taxa and 96 characters) was analyzed amniote groups that occur only within this time interval using TNT version 1.1 (Goloboff et al., 2008) using the implicit and which became extinct at or before the end-Triassic enumeration algorithm. Multistate characters 63, 70, 73, and mass extinction event (e.g., traversodontids, doswelliids, 75 were treated as additive because they represent nested tanystropheids, aetosaurs, phytosaurs; Abdala and Ribeiro, 2010; sets of homologies. Zero branch length nodes were collapsed Liu and Olsen, 2010; Desojo et al., 2013; Stocker and Butler, following the search (Coddington and Scharff, 1994). Absolute 2013; Sues et al., 2013; Pritchard et al., 2015). Although restricted and GC bootstrap frequencies were calculated after 10,000 to the Triassic, these groups achieved high morphological pseudoreplicates. GC bootstrap frequencies are the difference diversity and taxonomic richness, and some of them become key between the frequencies with which the original group and ecological components of their communities
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