DOCSLIB.ORG

Our Museum Dinosaurs

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Our Museum Dinosaurs Our Museum Dinosaurs Coelophysis Tyrannosaurus Means: ‘hollow form’ Means: ‘tyrant lizard’ Say it: seel-oh-FIE-sis Say it: tie-ran-oh-SORE-us Where found: USA Where found: USA, Canada Type: Theropod Type: Theropod Length: 3m Length: 12m Height: 2m Height: 3.6m Weight: 27kg Weight: 8,300kg How it moved: walked on two legs, may have run How it moved: swiftly on two legs Teeth: 60 saw-edged, bone-crushing, pointed Teeth: small and sharp teeth in immensely strong jaws Type of feeder: CARNIVORE Type of feeder: CARNIVORE + SCAVENGER Food: small reptiles and insects Food: all other animals When it lived: 225-220 million years ago When it lived: 68-66 million years ago In the museum In the museum Models of Coelophysis Full size replica of its skull REAL fossil footprints Polacanthus Edmontosaurus Means: ‘many prickles’ Means: ‘Edmonton lizard’ Say it: pole-a-CAN-thus Say it: ed-mon-toe-SORE-us Where found: England Where found: North America Type: Ankylosaur Type: Hadrosaur Length: 5m Length: 13m Height: 1m Height: 3.5m Weight: 2 tonnes Weight: 3,400kg How it moved: walked on four legs How it moved: on two or four legs Teeth: small Teeth: horny beak, 200 grinding cheek teeth Type of feeder: HERBIVORE Type of feeder: HERBIVORE Food: plants Food: pine needles, seeds, twigs and leaves When it lived: 130-125 million years ago When it lived: 73-66 million years ago In the museum In the museum Partial skeleton of A REAL Edmontosaurus skeleton Polacanthus (in rock) Fossil Edmontosaurus skin imprint Hypsilophodon Dracoraptor Means: ‘high-crested tooth’ Means: ‘dragon robber’ Say it: hip-sih-LOW-foh-don Say it: DRAY-co-RAP-tor Where found: Isle of Wight, England Where found: Wales Type: Ornithiscian (orn-i-thi-SHE-an) Type: Theropod Length: around 3m Length: 1.8m Height: around 1m Height: 0.8m (80cm) Weight: around 25kg Weight: 20kg How it moved: walked or ran on two legs How it moved: swiftly on two legs Teeth: small pointed serrated teeth Teeth: horny beak, c. 45 broad, chisel-like teeth Type of feeder: CARNIVORE Type of feeder: HERBIVORE Food: insects, small reptiles, fish Food: plants growing close to the ground When it lived: 201 million years ago When it lived: 130-125 million years ago In the museum Fossil skeleton and model In the museum Dracoraptor was one of the most recently A replica Hypsilophodon discovered dinosaurs in the UK skeleton and was described by our staff. Plateosaurus Oviraptor Means: ‘broad lizard Means: ‘egg thief’ Say it: plat-ee-o-SORE-us Say it: oh-vee-RAP-tor Where found: Germany Where found: Mongolia Type: Sauropodomorph Type: Theropod Length: 6m Length: 1m Height: 3m Height: 2m Weight: 2000kg Weight: 20kg How it moved: walked on two legs How it moved: walked on two legs Teeth: beak, but no teeth Teeth: many small, leaf-shaped, crushing teeth Type of feeder: OMNIVORE Type of feeder: HERBIVORE Food: small fish, molluscs, or hard fruit Food: plants When it lived: 85-75 million years ago When it lived: 214-204 million years ago In the museum In the museum Fossil Oviraptor egg It was first thought to be an egg eater, Plateosaurus skeleton cast but their fossils were then discovered sitting on nests, protecting them. Triceratops Neovenator Means: ‘three horned face’ Means: ‘new hunter’ Say it: tri-SERA-tops Say it: nee-o-ven-a-tor Where found: USA Where found: England Type: Ceratopsian Type: Theropod Length: 8.5m Length: 6m Height: 3m Height: 2.5m Weight: 8,000kg Weight: 700kg How it moved: walked and ran on two legs How it moved: walked slowly on four legs Teeth: around 70 large curved teeth Teeth: strong narrow beak with ridged back Type of feeder: CARNIVORE teeth for slicing tough plants Food: smaller dinosaurs Type of feeder: HERBIVORE When it lived: 130-125 million years ago Food: low-growing plants, ferns and cycads When it lived: 68-66 million years ago In the museum In the museum Replica skeleton and REAL footprints Fossil Triceratops horn Similar to a dinosaur that lived in Wales 210 million years ago Archaeopteryx Iguanodon Means: ‘ancient wing’ Means: ‘iguana tooth’ Say it: ark-ee-OPT-er-ix Say it: ig-WHA-noh-don Where found: Germany Where found: England and Europe Type: Theropod Type: Hadrosaur Length: 0.5m (50cm) Length: 10m Height: 0.2m (20cm) Height: 3-5m Weight: 0.6kg (600g) Weight: 4,500kg How it moved: walked slowly on 2 legs & ran fast How it moved: on 2 legs and by flying on 4 legs Teeth: many small conical teeth Teeth: chisel-shaped teeth and horny beak Type of feeder: CARNIVORE/INSECTIVORE Type of feeder: HERBIVORE Food: small reptiles, mammals and insects. Food: plants When it lived: 150 million years ago When it lived: 140-110 million years ago In the museum In the museum Replica Fossil skeleton Fossil bones Model of Archaeopteryx Name: Means: Say it: Where found: Type: Design your own! Length: Height: Weight: How it moved: Teeth: Type of feeder: Food: When it lived:.
Load more

Recommended publications
  • 200 Million-Year-Old Jurassic Dinosaur Uncovered in Wales 20 January 2016
    200 million-year-old Jurassic dinosaur uncovered in Wales 20 January 2016 balance. It lived at the beginning of the Jurassic Period (201 million years ago), at the time when south Wales was a coastal region like it is today. However, at the time, the climate was much warmer, and dinosaurs were just starting to diversify. The new specimen represents the most complete theropod from Wales, and may possibly represent one of the oldest known Jurassic dinosaurs in the UK or even in the world. Co-author Mr. Vidovic adds, "The Triassic-Jurassic extinction event is often credited for the later Artist's impression of Dracoraptor hanigani. Credit: Bob success of dinosaurs through the Jurassic and Nicholls Cretaceous, but previously we knew very little about dinosaurs at the start of this diversification and rise to dominance. Now we have Dracoraptor, a relatively complete two meter long juvenile A new carnivorous dinosaur species named theropod from the very earliest days of the Jurassic Dracoraptor hanigani uncovered in the south of in Wales." Wales is possibly the oldest known Jurassic dinosaur from the UK, according to a study More information: Martill DM, Vidovic SU, published January 20, 2016 in the open-access Howells C, Nudds JR (2016) The Oldest Jurassic journal PLOS ONE by David Martill from the Dinosaur: A Basal Neotheropod from the University of Portsmouth, England, and colleagues Hettangian of Great Britain. PLoS ONE 11(1): from National Museum Wales and University of e0145713. DOI: 10.1371/journal.pone.0145713 Manchester. The authors of this study that analyzed the dinosaur skull and bones, discovered in 2014 on a Provided by Public Library of Science beach near Penarth, Wales, conclude it is a new species that they have named Dracoraptor hanigani.
    [Show full text]
  • A Comprehensive Anatomical And
    Journal of Paleontology, Volume 94, Memoir 78, 2020, p. 1–103 Copyright © 2020, The Paleontological Society. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/ licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited. 0022-3360/20/1937-2337 doi: 10.1017/jpa.2020.14 A comprehensive anatomical and phylogenetic evaluation of Dilophosaurus wetherilli (Dinosauria, Theropoda) with descriptions of new specimens from the Kayenta Formation of northern Arizona Adam D. Marsh1,2 and Timothy B. Rowe1 1Jackson School of Geosciences, the University of Texas at Austin, 2305 Speedway Stop C1160, Austin, Texas 78712, USA <[email protected]><[email protected]> 2Division of Resource Management, Petrified Forest National Park, 1 Park Road #2217, Petrified Forest, Arizona 86028, USA Abstract.—Dilophosaurus wetherilli was the largest animal known to have lived on land in North America during the Early Jurassic. Despite its charismatic presence in pop culture and dinosaurian phylogenetic analyses, major aspects of the skeletal anatomy, taxonomy, ontogeny, and evolutionary relationships of this dinosaur remain unknown. Skeletons of this species were collected from the middle and lower part of the Kayenta Formation in the Navajo Nation in northern Arizona. Redescription of the holotype, referred, and previously undescribed specimens of Dilophosaurus wetherilli supports the existence of a single species of crested, large-bodied theropod in the Kayenta Formation. The parasagittal nasolacrimal crests are uniquely constructed by a small ridge on the nasal process of the premaxilla, dorsoventrally expanded nasal, and tall lacrimal that includes a posterior process behind the eye.
    [Show full text]
  • CPY Document
    v^ Official Journal of the Biology Unit of the American Topical Association 10 Vol. 40(4) DINOSAURS ON STAMPS by Michael K. Brett-Surman Ph.D. Dinosaurs are the most popular animals of all time, and the most misunderstood. Dinosaurs did not fly in the air and did not live in the oceans, nor on lake bottoms. Not all large "prehistoric monsters" are dinosaurs. The most famous NON-dinosaurs are plesiosaurs, moso- saurs, pelycosaurs, pterodactyls and ichthyosaurs. Any name ending in 'saurus' is not automatically a dinosaur, for' example, Mastodonto- saurus is neither a mastodon nor a dinosaur - it is an amphibian! Dinosaurs are defined by a combination of skeletal features that cannot readily be seen when the animal is fully restored in a flesh reconstruction. Because of the confusion, this compilation is offered as a checklist for the collector. This topical list compiles all the dinosaurs on stamps where the actual bones are pictured or whole restorations are used. It excludes footprints (as used in the Lesotho stamps), cartoons (as in the 1984 issue from Gambia), silhouettes (Ascension Island # 305) and unoffi- cial issues such as the famous Sinclair Dinosaur stamps. The name "Brontosaurus", which appears on many stamps, is used with quotation marks to denote it as a popular name in contrast to its correct scientific name, Apatosaurus. For those interested in a detailed encyclopedic work about all fossils on stamps, the reader is referred to the forthcoming book, 'Paleontology - a Guide to the Postal Materials Depicting Prehistoric Lifeforms' by Fran Adams et. al. The best book currently in print is a book titled 'Dinosaur Stamps of the World' by Baldwin & Halstead.
    [Show full text]
  • Psittacine Beak and Feather Disease (Or Psittacine Circovirus, PCV)
    Psittacine beak and feather disease (or psittacine circovirus, PCV) Published by The recent diagnosis of psittacine beak and feather disease in wild Biosecurity Unit parrots is a cause of concern to the Department of Conservation. It Department of Conservation was diagnosed in a wild eastern rosella in the Wellington region in PO Box 12–416 Wellington, New Zealand August 2003. This disease is caused by a highly infectious virus and April 2004 affects the skin, feathers and immune system of parrots. There is po- tential for the disease to be transmitted to other wild parrots, in par- ticular New Zealand’s native species, such as the endangered kakapo and kaka. The potential impact of this disease on these spe- cies is unknown as it has affected parrot species in other countries in unpredictable patterns. However, the disease, also known as psit- tacine circovirus (PCV), could decimate the already depleted populations of our treasured native parrots and it therefore repre- sents a significant threat to biodiversity. What is psittacine beak and What happens if birds are feather disease? infected with this disease? Psittacine beak and feather disease Three forms of the disease exist: per- (also known as psittacine circovirus, acute (very sudden onset), acute (sud- PCV) is a highly infectious viral dis- den onset) and chronic (long term). ease of parrots that can cause high ju- The peracute form affects neonatal venile mortality, or long-term immu- (baby) parrots and causes septicae- Parrot infected with psittacine nological suppression, feather abnor- mia, pneumonia, enteritis (inflam- beak and feather disease. Photograph: Mary Wagner malities and (in cockatoos) beak rot.
    [Show full text]
  • Beak and Feather Disease Viru
    Fact sheet Beak and feather disease virus (BFDV) is the causative agent of psittacine beak and feather disease (PBFD), an endemic disease in Australia’s wild parrot populations. Descriptions of parrots with feather loss consistent with the disease date back to the late 1800s (Ashby 1907). The virus is believed to have originated in Australia sometime following the separation of the continent from Gondwanaland, with spread to other parts of the world with modern movement of parrots as pet and aviary species . It has the potential to impact on several endangered Australian and non-Australian parrot populations and is listed as a key threatening process by the Australian government. Of late, the virus also has been identified in various non-psittacine species . Beak and feather disease virus is a 14 to 16 nm non-enveloped icosahedral DNA virus belonging to the family Circoviridae. Formerly, it was believed that the circoviruses recovered from a diverse range of psittacines were all antigenically similar. Doubt was cast on this theory when a virus that appeared to be serologically and genetically different was isolated from cockatiels (Nymphicus hollandicus) (Shearer et al. 2008). More recent research appears to indicate that psittacine circoviruses can be divided into two species and multiple viral strains. Based on work by Varsani et al. (2011), BFDV contains 14 strains, while budgerigar circovirus (BCV), a newly defined species to date only found in budgerigars (Melopsittacus undulates), contains three strains. However, it is likely that this number will continue to increase as shown by the discovery of two new distinct BFDV lineages in orange-bellied parrots (Neophema chrysogaster) (Peters et al.
    [Show full text]
  • Dino Cards Project D E F List B
    Daanosaurus Efraasia Dacentrurus Einiosaurus "Dachongosaurus" – nomen nudum Ekrixinatosaurus Daemonosaurus Elachistosuchus – a rhynchocephalian Dahalokely Elaltitan Dakosaurus – a metriorhynchid crocodilian Elaphrosaurus Dakotadon Elmisaurus Dakotaraptor Elopteryx - nomen dubium Daliansaurus Elosaurus – junior synonym of Brontosaurus "Damalasaurus" – nomen nudum Elrhazosaurus Dandakosaurus - nomen dubium "Elvisaurus" – nomen nudum; Cryolophosaurus Danubiosaurus – junior synonym of Struthiosaurus Emausaurus "Daptosaurus" – nomen nudum; early manuscript name for Deinonychus Embasaurus - theropoda incertae sedis Darwinsaurus - possible junior synonym of Huxleysaurus Enigmosaurus Dashanpusaurus Eoabelisaurus Daspletosaurus Eobrontosaurus – junior synonym of Brontosaurus Dasygnathoides – a non-dinosaurian archosaur, junior synonym Eocarcharia of Ornithosuchus Eoceratops – junior synonym of Chasmosaurus "Dasygnathus" – preoccupied name, now known as Dasygnathoides Eocursor Datanglong Eodromaeus Datonglong "Eohadrosaurus" – nomen nudum; Eolambia Datousaurus Eolambia Daurosaurus – synonym of Kulindadromeus Eomamenchisaurus Daxiatitan Eoplophysis - Dinosauria indet. Deinocheirus Eoraptor Deinodon – possibly Gorgosaurus Eosinopteryx - Avialae Deinonychus Eotrachodon Delapparentia - probable junior synonym of Iguanodon Eotriceratops Deltadromeus Eotyrannus Demandasaurus Eousdryosaurus Denversaurus Epachthosaurus Deuterosaurus – a therapsid Epanterias – may be Allosaurus Diabloceratops "Ephoenosaurus" – nomen nudum; Machimosaurus (a crocodilian) Diamantinasaurus
    [Show full text]
  • List of Shorebird Profiles
    List of Shorebird Profiles Pacific Central Atlantic Species Page Flyway Flyway Flyway American Oystercatcher (Haematopus palliatus) •513 American Avocet (Recurvirostra americana) •••499 Black-bellied Plover (Pluvialis squatarola) •488 Black-necked Stilt (Himantopus mexicanus) •••501 Black Oystercatcher (Haematopus bachmani)•490 Buff-breasted Sandpiper (Tryngites subruficollis) •511 Dowitcher (Limnodromus spp.)•••485 Dunlin (Calidris alpina)•••483 Hudsonian Godwit (Limosa haemestica)••475 Killdeer (Charadrius vociferus)•••492 Long-billed Curlew (Numenius americanus) ••503 Marbled Godwit (Limosa fedoa)••505 Pacific Golden-Plover (Pluvialis fulva) •497 Red Knot (Calidris canutus rufa)••473 Ruddy Turnstone (Arenaria interpres)•••479 Sanderling (Calidris alba)•••477 Snowy Plover (Charadrius alexandrinus)••494 Spotted Sandpiper (Actitis macularia)•••507 Upland Sandpiper (Bartramia longicauda)•509 Western Sandpiper (Calidris mauri) •••481 Wilson’s Phalarope (Phalaropus tricolor) ••515 All illustrations in these profiles are copyrighted © George C. West, and used with permission. To view his work go to http://www.birchwoodstudio.com. S H O R E B I R D S M 472 I Explore the World with Shorebirds! S A T R ER G S RO CHOOLS P Red Knot (Calidris canutus) Description The Red Knot is a chunky, medium sized shorebird that measures about 10 inches from bill to tail. When in its breeding plumage, the edges of its head and the underside of its neck and belly are orangish. The bird’s upper body is streaked a dark brown. It has a brownish gray tail and yellow green legs and feet. In the winter, the Red Knot carries a plain, grayish plumage that has very few distinctive features. Call Its call is a low, two-note whistle that sometimes includes a churring “knot” sound that is what inspired its name.
    [Show full text]
  • A Revised Taxonomy of the Iguanodont Dinosaur Genera and Species
    ARTICLE IN PRESS + MODEL Cretaceous Research xx (2007) 1e25 www.elsevier.com/locate/CretRes A revised taxonomy of the iguanodont dinosaur genera and species Gregory S. Paul 3109 North Calvert Station, Side Apartment, Baltimore, MD 21218-3807, USA Received 20 April 2006; accepted in revised form 27 April 2007 Abstract Criteria for designating dinosaur genera are inconsistent; some very similar species are highly split at the generic level, other anatomically disparate species are united at the same rank. Since the mid-1800s the classic genus Iguanodon has become a taxonomic grab-bag containing species spanning most of the Early Cretaceous of the northern hemisphere. Recently the genus was radically redesignated when the type was shifted from nondiagnostic English Valanginian teeth to a complete skull and skeleton of the heavily built, semi-quadrupedal I. bernissartensis from much younger Belgian sediments, even though the latter is very different in form from the gracile skeletal remains described by Mantell. Currently, iguanodont remains from Europe are usually assigned to either robust I. bernissartensis or gracile I. atherfieldensis, regardless of lo- cation or stage. A stratigraphic analysis is combined with a character census that shows the European iguanodonts are markedly more morpho- logically divergent than other dinosaur genera, and some appear phylogenetically more derived than others. Two new genera and a new species have been or are named for the gracile iguanodonts of the Wealden Supergroup; strongly bipedal Mantellisaurus atherfieldensis Paul (2006. Turning the old into the new: a separate genus for the gracile iguanodont from the Wealden of England. In: Carpenter, K. (Ed.), Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs.
    [Show full text]
  • Dinosaurs British Isles
    DINOSAURS of the BRITISH ISLES Dean R. Lomax & Nobumichi Tamura Foreword by Dr Paul M. Barrett (Natural History Museum, London) Skeletal reconstructions by Scott Hartman, Jaime A. Headden & Gregory S. Paul Life and scene reconstructions by Nobumichi Tamura & James McKay CONTENTS Foreword by Dr Paul M. Barrett.............................................................................10 Foreword by the authors........................................................................................11 Acknowledgements................................................................................................12 Museum and institutional abbreviations...............................................................13 Introduction: An age-old interest..........................................................................16 What is a dinosaur?................................................................................................18 The question of birds and the ‘extinction’ of the dinosaurs..................................25 The age of dinosaurs..............................................................................................30 Taxonomy: The naming of species.......................................................................34 Dinosaur classification...........................................................................................37 Saurischian dinosaurs............................................................................................39 Theropoda............................................................................................................39
    [Show full text]
  • A Juvenile Cf. Edmontosaurus Annectens (Ornithischia, Hadrosauridae) Femur Documents a Previously Unreported Intermediate Growth Stage for This Taxon Andrew A
    Vertebrate Anatomy Morphology Palaeontology 7:59–67 59 ISSN 2292-1389 A juvenile cf. Edmontosaurus annectens (Ornithischia, Hadrosauridae) femur documents a previously unreported intermediate growth stage for this taxon Andrew A. Farke1,2,3,* and Eunice Yip2 1Raymond M. Alf Museum of Paleontology, 1175 West Baseline Road, Claremont, CA, 91711, USA 2The Webb Schools, 1175 West Baseline Road, Claremont, CA, 91711, USA 3Dinosaur Institute, Natural History Museum of Los Angeles County, 900 Exposition Blvd. Los Angeles, CA, 90007, USA; [email protected] Abstract: A nearly complete, but isolated, femur of a small hadrosaurid from the Hell Creek Formation of Montana is tentatively referred to Edmontosaurus annectens. At 28 cm long, the element can be classified as likely that from an ‘early juvenile’ individual, approximately 24% of the maximum known femur length for this species. Specimens from this size range and age class have not been described previously for E. annectens. Notable trends with increasing body size include increasingly distinct separation of the femoral head and greater trochanter, relative increase in the size of the cranial trochanter, a slight reduction in the relative breadth of the fourth trochanter, and a relative increase in the prominence of the cranial intercondylar groove. The gross profile of the femoral shaft is fairly consistent between the smallest and largest individuals. Although an ontogenetic change from relatively symmetrical to an asymmetrical shape in the fourth trochanter has been suggested previously, the new juvenile specimen shows an asymmetric fourth tro- chanter. Thus, there may not be a consistent ontogenetic pattern in trochanteric morphology. An isometric relationship between femoral circumference and femoral length is confirmed for Edmontosaurus.
    [Show full text]
  • The Dinosaurs Transylvanian Province in Hungary
    COMMUNICATIONS OF THE YEARBOOK OF THE ROYAL HUNGARIAN GEOLOGICAL IMPERIAL INSTITUTE ================================================================== VOL. XXIII, NUMBER 1. ================================================================== THE DINOSAURS OF THE TRANSYLVANIAN PROVINCE IN HUNGARY. BY Dr. FRANZ BARON NOPCSA. WITH PLATES I-IV AND 3 FIGURES IN THE TEXT. Published by The Royal Hungarian Geological Imperial Institute which is subject to The Royal Hungarian Agricultural Ministry BUDAPEST. BOOK-PUBLISHER OF THE FRANKLIN ASSOCIATION. 1915. THE DINOSAURS OF THE TRANSYLVANIAN PROVINCE IN HUNGARY. BY Dr. FRANZ BARON NOPCSA. WITH PLATES I-IV AND 3 FIGURES IN THE TEXT. Mit. a. d. Jahrb. d. kgl. ungar. Geolog. Reichsanst. XXIII. Bd. 1 heft I. Introduction. Since it appears doubtful when my monographic description of the dinosaurs of Transylvania1 that formed my so-to-speak preparatory works to my current dinosaur studies can be completed, due on one hand to outside circumstances, but on the other hand to the new arrangement of the vertebrate material in the kgl. ungar. geologischen Reichsanstalt accomplished by Dr. KORMOS, the necessity emerged of also exhibiting some of the dinosaur material located here, so that L. v. LÓCZY left the revision to me; I view the occasion, already briefly anticipating my final work at this point, to give diagnoses of the dinosaurs from the Transylvanian Cretaceous known up to now made possible from a systematic division of the current material, as well as to discuss their biology. The reptile remains known from the Danian of Transylvania will be mentioned only incidentally. Concerning the literature, I believe in refraining from more exact citations, since this work presents only a preliminary note.
    [Show full text]
  • A Re-Evaluation of the Enigmatic Dinosauriform Caseosaurus Crosbyensis from the Late Triassic of Texas, USA and Its Implications for Early Dinosaur Evolution
    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.
    [Show full text]