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University of Birmingham Description and phylogenetic placement of a new marine species of phytosaur (Archosauriformes: Phytosauria) from the Late Triassic of Austria Butler, Richard; Jones, Andrew; Buffetaut, Eric; Mandl, Gerhard; Scheyer, Torsten; Schultz, Ortwin DOI: 10.1093/zoolinnean/zlz014 License: Other (please specify with Rights Statement) Document Version Peer reviewed version Citation for published version (Harvard): Butler, R, Jones, A, Buffetaut, E, Mandl, G, Scheyer, T & Schultz, O 2019, 'Description and phylogenetic placement of a new marine species of phytosaur (Archosauriformes: Phytosauria) from the Late Triassic of Austria', Zoological Journal of the Linnean Society, vol. 187, no. 1, pp. 198-228. https://doi.org/10.1093/zoolinnean/zlz014 Link to publication on Research at Birmingham portal Publisher Rights Statement: Checked for eligibility 04/02/2019 This is a pre-copyedited, author-produced version of an article accepted for publication in Zoological Journal of the Linnean Society following peer review. The version of record Richard J Butler, Andrew S Jones, Eric Buffetaut, Gerhard W Mandl, Torsten M Scheyer, Ortwin Schultz, Description and phylogenetic placement of a new marine species of phytosaur (Archosauriformes: Phytosauria) from the Late Triassic of Austria, Zoological Journal of the Linnean Society, Volume 187, Issue 1, September 2019, Pages 198–228, is available online at: https://doi.org/10.1093/zoolinnean/zlz014. 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. 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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: 09. Oct. 2021 Zoological Journal of the Linnean Society A NEW SPECIES OF MYSTRIOSUCHUS (ARCHOSAURIFORMES, PHYTOSAURIA) FROM THE LATE TRIASSIC OF AUSTRIA Journal: Zoological Journal of the Linnean Society Manuscript ID ZOJ-09-2018-3439.R1 Manuscript Type:ForOriginal Review Article Only Anatomy, Upper Triassic < Palaeontology, Archosauria < Taxa, Keywords: Phylogenetics, Taxonomy Phytosaurs are a group of carnivorous, semi-aquatic archosaurian reptiles that attained an almost global distribution during the Late Triassic. We describe a new species of the phytosaur genus Mystriosuchus from the Norian Dachstein Limestone of Austria, from a marine lagoonal depositional environment. The new Austrian material comprises remains of at least four individuals of similar size (c. 4 metres in total length) found in association but disarticulated, and includes one complete and two partial skulls, as well as postcrania. All of these specimens apparently represent a single taxon, which is distinguished by numerous anatomical features from the two previously named Abstract: Mystriosuchus species. Maximum parsimony analysis of a comprehensive morphological dataset provides strong statistical support for the phylogenetic position of the new Austrian taxon within Mystriosuchus, as the sister taxon to a clade comprising M. planirostris and M. westphali. Histological analysis suggests that the Austrian phytosaur specimens represent individuals that were at least eight years old at time of death, but which had not yet reached skeletal maturity. Taphonomic and palaeoenvironmental data suggest that these phytosaurs were living within the marine lagoon in which they were preserved, providing the strongest evidence to date of marine adaptations in phytosaurs. Page 1 of 71 Zoological Journal of the Linnean Society 1 1 2 3 Abstract. Phytosaurs are a group of carnivorous, semi-aquatic archosaurian reptiles that 4 5 6 attained an almost global distribution during the Late Triassic. We describe a new species of 7 8 the phytosaur genus Mystriosuchus from the Norian Dachstein Limestone of Austria, from a 9 10 marine lagoonal depositional environment. The new Austrian material comprises remains of 11 12 at least four individuals of similar size (c. 4 metres in total length) found in association but 13 14 15 disarticulated, and includes one complete and two partial skulls, as well as postcrania. All of 16 17 these specimens apparently represent a single taxon, which is distinguished by numerous 18 19 anatomical features from the two previously named Mystriosuchus species. Maximum 20 21 For Review Only 22 parsimony analysis of a comprehensive morphological dataset provides strong statistical 23 24 support for the phylogenetic position of the new Austrian taxon within Mystriosuchus, as the 25 26 sister taxon to a clade comprising M. planirostris and M. westphali. Histological analysis 27 28 29 suggests that the Austrian phytosaur specimens represent individuals that were at least eight 30 31 years old at time of death, but which had not yet reached skeletal maturity. Taphonomic and 32 33 palaeoenvironmental data suggest that these phytosaurs were living within the marine lagoon 34 35 in which they were preserved, providing the strongest evidence to date of marine adaptations 36 37 38 in phytosaurs. 39 40 41 42 Key words: Phytosauria, Triassic, Austria, phylogeny, bone histology 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 Zoological Journal of the Linnean Society Page 2 of 71 2 1 2 3 INTRODUCTION 4 5 6 7 8 Phytosaurs are an important group of early archosauriform reptiles that were nearly globally 9 10 distributed during the Late Triassic, and which were remarkably morphologically convergent 11 12 with modern crocodilians (Stocker & Butler, 2013). Phytosaur fossils are most commonly 13 14 15 recovered from fluvial and lacustrine depositional environments, and are typically 16 17 reconstructed as carnivorous and semi-aquatic components of terrestrial ecosystems (Stocker 18 19 & Butler, 2013). However, a small number of phytosaur specimens have been recovered from 20 21 For Review Only 22 Upper Triassic marine deposits in Austria and Italy (Buffetaut, 1993; Renesto & Paganoni, 23 24 1998; Gozzi & Renesto, 2003; Renesto, 2008). The majority of these marine specimens have 25 26 been referred to the genus Mystriosuchus, which was first described from the terrestrial 27 28 29 deposits of the Löwenstein Formation of southwest Germany (Meyer, 1863; Huene, 1915; 30 31 Hungerbühler, 1998, 2002; Hungerbühler & Hunt, 2000). However, though the Italian 32 33 phytosaur material has received detailed study (Renesto & Paganoni, 1998; Gozzi & Renesto, 34 35 2003; Renesto, 2008), the Austrian phytosaur material has only been mentioned briefly in the 36 37 38 literature (Buffetaut, 1993; Stocker & Butler, 2013). 39 40 The Austrian specimens were collected from the Totes Gebirge (‘dead mountains’), a 41 42 group of mountains situated in northwestern Styria (Steiermark) and southern Upper Austria 43 44 45 (Oberösterreich), which form part of the Northern Calcareous Alps. In September 1980, a 46 47 local speleologist, Sepp Steinberger, made a discovery of phytosaur fossils in the Totes 48 49 Gebirge, close to the mountain Hochweiß. The Department of Geology and Paleontology of 50 51 52 the Natural History Museum in Vienna (NHMW) subsequently arranged excavation of the 53 54 material, which took place July 12th–16th 1982 (Fig. 1). The excavation was completed by 55 56 Ortwin Schultz, Robert Seemann, Georg Sverak and Walter Prenner of the NHMW, 57 58 supported by Sepp Steinberger and Johann Segl, members of the local caving club. The 59 60 Page 3 of 71 Zoological Journal of the Linnean Society 3 1 2 3 recovered rock and fossils were transported off the mountains by helicopter, with the 4 5 6 excavation receiving considerable coverage in the local media. 7 8 Subsequent preparation of the fossils took place at NHMW, where several specimens 9 10 are now on permanent display. Buffetaut (1993) briefly mentioned this material, referring it 11 12 to Mystriosuchus planirostris, and figured a relatively complete skull. However, no 13 14 15 subsequent description or detailed taxonomic assessment of this material has been published. 16 17 Here, we describe this important phytosaur material in detail and assess its phylogenetic 18 19 position and taxonomic affinities, identifying it as a new species of the genus Mystriosuchus. 20 21 For Review Only 22 23 24 INSTITUTIONAL ABBREVIATIONS 25 26 AMNH, American Museum of Natural History, New York, USA; GPIT, Palaeontological 27 28 29 Collection of the University of Tübingen, Germany; MB, Museum für Naturkunde, Berlin, 30 31 Germany; MCSNB, Museo Civico di Scienze Naturali “E. Caffi” di Bergamo, Lombardy, 32 33 Italy; NHMW, Naturhistorisches Museum Wien, Vienna, Austria; NMMNH, New Mexico 34 35 Museum of Natural History & Science, Albuquerque, USA; SMNS, Staatliches Museum für 36 37 38 Naturkunde, Stuttgart, Germany. 39 40 41 42 43 44 45 GEOLOGICAL SETTING 46 47 48 49 The Totes Gebirge is a large karst plateau covering approximately 1130 square kilometres, 50 51 52 with altitudes of between 1400 and 1600 m in the western part and up to 2500 m in the 53 54 eastern part. The phytosaur remains described here were recovered at an altitude of 1970 m in 55 56 the southern part of the plateau.