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New Dinosauriform (Ornithodira, Dinosauromorpha) Record from the Upper Triassic of Southern Brazil Author(s): Rodrigo Temp Müller , Max Cardoso Langer , Alex Sandro Schiller Aires and Sérgio Dias-da- silva Source: Paleontological Research, 18(2):118-121. 2014. Published By: The Palaeontological Society of Japan DOI: http://dx.doi.org/10.2517/2014PR012 URL: http://www.bioone.org/doi/full/10.2517/2014PR012 BioOne (www.bioone.org) is a nonprofit, online aggregation of core research in the biological, ecological, and environmental sciences. BioOne provides a sustainable online platform for over 170 journals and books published by nonprofit societies, associations, museums, institutions, and presses. Your use of this PDF, the BioOne Web site, and all posted and associated content indicates your acceptance of BioOne’s Terms of Use, available at www.bioone.org/page/terms_of_use. Usage of BioOne content is strictly limited to personal, educational, and non-commercial use. Commercial inquiries or rights and permissions requests should be directed to the individual publisher as copyright holder. BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting authors, nonprofit publishers, academic institutions, research libraries, and research funders in the common goal of maximizing access to critical research. Paleontological Research, vol. 18, no. 2, pp. 118–121, April 1, 2014 © by the Palaeontological Society of Japan doi:10.2517/2014PR012 New dinosauriform (Ornithodira, Dinosauromorpha) record from the Upper Triassic of Southern Brazil 1 2 3 RODRIGO TEMP MÜLLER , MAX CARDOSO LANGER , ALEX SANDRO SCHILLER AIRES AND SÉRGIO DIAS-DA-SILVA1 1Laboratório de Paleobiologia, Campus de São Gabriel, Universidade Federal do Pampa, Avenida Antônio Trilha, 1847, Bairro Centro, CEP 97.300-000, São Gabriel, Rio Grande do Sul, Brazil (e-mail: [email protected]) 2Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo (USP), Av. Bandeirantes, 3900, CEP 14040-901, Ribeirão Preto, São Paulo, Brazil 3Universidade Regional Integrada do Alto Uruguai e das Missões (URI) - Campus de Frederico Westphalen, Rio Grande do Sul, Brazil Received September 13, 2013; Revised manuscript accepted November 19, 2013 Key words: Carnian, Non-dinosaur dinosauriform, Paraná Basin, Santa Maria Formation, silesaurid Introduction silesaurid affinity. Institutional abbreviations.—UNIPAMPA, Universi- Dinosauriformes includes the most recent common dade Federal do Pampa, São Gabriel, Brazil. ancestor of Marasuchus lilloensis and Dinosauria, and all taxa stemming from it (Novas, 1992). The origin of this Systematic palaeontology group and its diversification have been the subject of extensive studies in recent years (Langer et al., 2010; Archosauria Cope, 1869 Langer et al., 2013), especially because it includes the Ornithodira Gauthier, 1986 dinosaur lineage, one of the most diverse groups of Dinosauromorpha Benton, 1985 Mesozoic tetrapods (Irmis, 2011; Novas et al., 2011). The Dinosauriformes Novas, 1992 oldest Dinosauriformes came from the upper Anisian of Figure 1 Tanzania (Nesbitt et al., 2010) and the Ladinian of Argentina (Romer, 1972a, b; Arcucci, 1987; Sereno and Material.—UNIPAMPA-0632, partial left femur. Arcucci, 1993) and recent studies demonstrated that non- Locality and Horizon.—Janner Site, 2 km west of dinosaur dinosauriforms shared environments with dino- Agudo, Rio Grande do Sul, Brazil. Upper portion of the saurs until the end of the Triassic (Novas and Ezcurra, Hyperodapedon Assemblage Zone (sensu Langer et al., 2005; Ezcurra, 2006; Nesbitt et al., 2010; Langer et al., 2007), upper Carnian of the Paraná Basin. 2013). Yet, the small number of available specimens Description.—The partial left femur is 110 mm long regarded as early members or possible ancestors of and sigmoid in cranial and lateral views. The proximal Dinosauria still brings great uncertainty regarding both extremity is missing, and only the distal portion of the origins and phylogenetic relationships of the group. “crest-like” fourth trochanter is preserved (Figure 1B-C). In the present contribution, we report the occurrence of The ‘lesser trochanter’ (Musculus iliofemuralis cranialis a new non-dinosaur dinosauriform specimen from the insertion) is seen on the lateral surface of the proximal Santa Maria Formation, a stratigraphic unit that congre- half of the bone as a slight proximodistally elongated gates the oldest unequivocal dinosauriform records from prominence that is completely connected to the shaft Brazil (Colbert, 1970; Langer et al., 1999; Kischlat, (Figure 1B and E). This condition differs from the knob- 1999; Da-Rosa et al., 2006; Cabreira et al., 2011), all of like ‘lesser trochanter’ of Pampadromaeus barberenai which are included within Dinosauria. One exception is (Cabreira et al., 2011), Saturnalia tupiniquim (Langer et the problematic Teyuwasu barberenai (Kischlat, 1999), al., 1999), and Sacisaurus agudoesis (Ferigolo and considered nomen dubium by Langer (2004) and revised Langer, 2007), in which the proximal portion is separated recently by Ezcurra (2012), which tentatively suggests a from the shaft by a cleft. The ‘trochanteric shelf’ is New dinosauriform femur from Brazil 119 Figure 1. Photographs and illustrations of specimen UNIPAMPA-0632. A, cranial view; B, lateral view; C, caudomedial view; D, distal view, and E, caudolateral view. absent (Figure 1E), as in Sacisaurus and differently from synapomorphies, including a popliteal fossa extending Pampadromaeus and Saturnalia. The popliteal fossa for proximally one-fourth to one-third the length of the extends for one-fourth to one-third of the shaft length femur, as observed in UNIPAMPA-0632. However, both (Figure 1C), as in Asilisaurus kongwe (Nesbitt et al., the composition and phylogenetic position of Silesauridae 2010), Eucoelophysis baldwini (Sullivan and Lucas, have been recently considered uncertain (Langer and 1999), Silesaurus opoloensis (Dzik, 2003), Sacisaurus Ferigolo, 2013), hampering the precise taxonomic attri- and Diodorus scytobrachion (Kammerer et al., 2012). bution of this specimen. Still, the absence of a protruding Some longitudinal grooves can be observed along the ‘lesser trochanter’ suggests a closer affinity to non-dino- cranial surface of the distal portion of the femur, which saur Dinosauriformes, given that all well known Triassic may correspond to points of insertion for the Musculus dinosaurs have that structure (Nesbitt, 2011; Langer and femorotibialis externus (Figure 1A). Ferigolo, 2013). The faunal content of the Janner, or Várzea do Agudo, Discussion and conclusion site resembles that of the Ischigualasto Formation, in northwestern Argentina, which shows a predominance of UNIPAMPA-0632 is assigned to Dinosauriformes due both Exaeretodon (Cabrera, 1943) and Hyperodapedon to the presence of a ‘lesser trochanter’ and a “crest-like” (Huxley in Murchison, 1859; p. 435, 436; Huxley, 1869). fourth trochanter. It does not bear any clear autapomor- [Note: The genus and species name Hyperodapedon gor- phic character, but differs from all previously known doni was introduced by Sir Roderick I. Murchison in dinosauromorphs from the Santa Maria Formation due 1859, in a postscript added in press (see References in the the combination of a ‘lesser trochanter’ completely con- present paper), the fossil having been sent by Murchison nected to the shaft and a longitudinally extensive to T. H. Huxley for identification. Murchison therein popliteal fossa. Therefore, it might represent a still attributed the name to Huxley. Consequently the genus unknown taxon from the upper portion of the Hyperoda- should be cited as Hyperodapedon Huxley in Murchison, pedon Assemblage Zone in Southern Brazil. 1859, and likewise the type species H. gordoni.] This Nesbitt et al. (2010) recognized an unnamed clade allows a direct biostratigraphic correlation and the prop- within Silesauridae, containing Asilisaurus, Eucoelophy- osition of a late Carnian age for the Janner Site (Martinez sis, Sacisaurus, and Silesaurus supported by about five et al., 2011). Because of the predominance of Exaeret- 120 Rodrigo Temp Müller et al. odon specimens, Langer et al. (2007) assigned that local- obiogeography of the earliest know dinosaur assemblages (late ity to the upper portions of the Hyperodapedon Carnian-earliest Norian). Historia Natural, Tercera Serie, vol. 2, Assemblage Zone, whereas the Sacisaurus agudoensis p. 49–71. Ferigolo, J. and Langer, M. C., 2007: A Late Triassic dinosauriform locality (also in the municipality of Agudo) belongs to from south Brazil and the origin of the ornithischian predentary the lower (upper Carnian/lower Norian) Riograndia bone. Historical Biology, vol. 19, p. 23–33. Assemblage Zone (Soares et al., 2011), within the Gauthier, J. A., 1986: Saurischian monophyly and the origin of birds. Caturrita Formation. Accordingly, UNIPAMPA-0632 is Memoirs of the California Academy of Sciences, vol. 8, p. 1–55. probably older than Sacisaurus agudoensis. Indeed, if Huxley, T. H., 1869: On Hyperodapedon. Quarterly Journal of the Geological Society of London, vol. 25, p. 138–152. UNIPAMPA-0632 corresponds to a Silesauridae, it Irmis, R. B., 2011: Evaluating hypotheses for the early diversification extends the occurrence of this clade to the Carnian of of dinosaurs. Earth and Environmental Science Transactions of Brazil. In global terms, the only two other putatively the Royal Society of Edinburgh, vol. 101,
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    A re-evaluation of the enigmatic dinosauriform Caseosaurus crosbyensis from the Late Triassic of Texas, USA and its implications for early dinosaur evolution MATTHEW G. BARON and MEGAN E. WILLIAMS Baron, M.G. and Williams, M.E. 2018. A re-evaluation of the enigmatic dinosauriform Caseosaurus crosbyensis from the Late Triassic of Texas, USA and its implications for early dinosaur evolution. Acta Palaeontologica Polonica 63 (1): 129–145. The holotype specimen of the Late Triassic dinosauriform Caseosaurus crosbyensis is redescribed and evaluated phylogenetically for the first time, providing new anatomical information and data on the earliest dinosaurs and their evolution within the dinosauromorph lineage. Historically, Caseosaurus crosbyensis has been considered to represent an early saurischian dinosaur, and often a herrerasaur. More recent work on Triassic dinosaurs has cast doubt over its supposed dinosaurian affinities and uncertainty about particular features in the holotype and only known specimen has led to the species being regarded as a dinosauriform of indeterminate position. Here, we present a new diagnosis for Caseosaurus crosbyensis and refer additional material to the taxon—a partial right ilium from Snyder Quarry. Our com- parisons and phylogenetic analyses suggest that Caseosaurus crosbyensis belongs in a clade with herrerasaurs and that this clade is the sister taxon of Dinosauria, rather than positioned within it. This result, along with other recent analyses of early dinosaurs, pulls apart what remains of the “traditional” group of dinosaurs collectively termed saurischians into a polyphyletic assemblage and implies that Dinosauria should be regarded as composed exclusively of Ornithoscelida (Ornithischia + Theropoda) and Sauropodomorpha. In addition, our analysis recovers the enigmatic European taxon Saltopus elginensis among herrerasaurs for the first time.
  • Gondwana Vertebrate Faunas of India: Their Diversity and Intercontinental Relationships

    Gondwana Vertebrate Faunas of India: Their Diversity and Intercontinental Relationships

    438 Article 438 by Saswati Bandyopadhyay1* and Sanghamitra Ray2 Gondwana Vertebrate Faunas of India: Their Diversity and Intercontinental Relationships 1Geological Studies Unit, Indian Statistical Institute, 203 B. T. Road, Kolkata 700108, India; email: [email protected] 2Department of Geology and Geophysics, Indian Institute of Technology, Kharagpur 721302, India; email: [email protected] *Corresponding author (Received : 23/12/2018; Revised accepted : 11/09/2019) https://doi.org/10.18814/epiiugs/2020/020028 The twelve Gondwanan stratigraphic horizons of many extant lineages, producing highly diverse terrestrial vertebrates India have yielded varied vertebrate fossils. The oldest in the vacant niches created throughout the world due to the end- Permian extinction event. Diapsids diversified rapidly by the Middle fossil record is the Endothiodon-dominated multitaxic Triassic in to many communities of continental tetrapods, whereas Kundaram fauna, which correlates the Kundaram the non-mammalian synapsids became a minor components for the Formation with several other coeval Late Permian remainder of the Mesozoic Era. The Gondwana basins of peninsular horizons of South Africa, Zambia, Tanzania, India (Fig. 1A) aptly exemplify the diverse vertebrate faunas found Mozambique, Malawi, Madagascar and Brazil. The from the Late Palaeozoic and Mesozoic. During the last few decades much emphasis was given on explorations and excavations of Permian-Triassic transition in India is marked by vertebrate fossils in these basins which have yielded many new fossil distinct taxonomic shift and faunal characteristics and vertebrates, significant both in numbers and diversity of genera, and represented by small-sized holdover fauna of the providing information on their taphonomy, taxonomy, phylogeny, Early Triassic Panchet and Kamthi fauna.