FACT SHEET: Megalosaurus

Total Page：16

File Type：pdf, Size：1020Kb

FACT SHEET: megalosaurus NAME: MEGALOSAURUS (MEG-ah-lo-SAW-rus), meaning: "Great Lizard" SIZE: 30 feet long, 10 feet tall (the size of a school bus), weighed 1 ton TYPE OF DIET: Carnivore (large sauropods, also a scavenger) WHEN: Early Jurassic period (181 - 169 million years ago) WHERE: England (United Kingdom) Megalosaurus lived about 181-169 million years ago. It was one the first dinosaur fossils ever discovered. A man named William Buckland first studied these ancient bones in England, and in 1824 he named the creature Megalosaurus, which means “great lizard”. He wrote the first scientific description of what would eventually be called a “dinosaur”. He only found pieces of a leg, shoulder, hip and jaw. From these pieces, he did his best to build the first picture of a dinosaur. And even though he didn’t have many bones to work with, he understood that Megalosaurus was a large, bipedal dinosaur. This means that it walked on two legs. Megalosaurus was a huge dinosaur. It grew up to 30 feet long, ten feet tall, and weighed about a ton. It had a strong, short neck and a large head. It had a thick, long tail, and heavy bones. Many paleontologists believe that it was clumsy walker. Its toes point inward and the prints seem to show that it wasn’t very agile. However, Megalosaurus could probably run very fast when it needed to. Megalosaurus was a carnivore, meaning that it hunted other animals for food. It had long, curved, serrated teeth that had jagged edges, like a saw. It was a fierce predator that could kill even large sauropods such as Diplodocus and Apatosaurus. It ate a lot of different kinds of animals. We do not know whether it moved about in groups or whether it spent most of its time alone. So far, only single bones have been found in a few places. Dinosaur Days TM © 2010 Distant Train, inc. (www.distanttrain.com) all rights reserved.

Copy Link

Recommended publications

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]
Dinosaur Species List E to M
Dinosaur Species List E to M E F G • Echinodon becklesii • Fabrosaurus australis • Gallimimus bullatus • Edmarka rex • Frenguellisaurus • Garudimimus brevipes • Edmontonia longiceps ischigualastensis • Gasosaurus constructus • Edmontonia rugosidens • Fulengia youngi • Gasparinisaura • Edmontosaurus annectens • Fulgurotherium australe cincosaltensis • Edmontosaurus regalis • Genusaurus sisteronis • Edmontosaurus • Genyodectes serus saskatchewanensis • Geranosaurus atavus • Einiosaurus procurvicornis • Gigantosaurus africanus • Elaphrosaurus bambergi • Giganotosaurus carolinii • Elaphrosaurus gautieri • Gigantosaurus dixeyi • Elaphrosaurus iguidiensis • Gigantosaurus megalonyx • Elmisaurus elegans • Gigantosaurus robustus • Elmisaurus rarus • Gigantoscelus • Elopteryx nopcsai molengraaffi • Elosaurus parvus • Gilmoreosaurus • Emausaurus ernsti mongoliensis • Embasaurus minax • Giraffotitan altithorax • Enigmosaurus • Gongbusaurus shiyii mongoliensis • Gongbusaurus • Eoceratops canadensis wucaiwanensis • Eoraptor lunensis • Gorgosaurus lancensis • Epachthosaurus sciuttoi • Gorgosaurus lancinator • Epanterias amplexus • Gorgosaurus libratus • Erectopus sauvagei • "Gorgosaurus" novojilovi • Erectopus superbus • Gorgosaurus sternbergi • Erlikosaurus andrewsi • Goyocephale lattimorei • Eucamerotus foxi • Gravitholus albertae • Eucercosaurus • Gresslyosaurus ingens tanyspondylus • Gresslyosaurus robustus • Eucnemesaurus fortis • Gresslyosaurus torgeri • Euhelopus zdanskyi • Gryponyx africanus • Euoplocephalus tutus • Gryponyx taylori • Euronychodon
[Show full text]
Back Matter (PDF)
Index Note: Page numbers in italic denote ﬁgures. Page numbers in bold denote tables. Abel, Othenio (1875–1946) Ashmolean Museum, Oxford, Robert Plot 7 arboreal theory 244 Astrodon 363, 365 Geschichte und Methode der Rekonstruktion... Atlantosaurus 365, 366 (1925) 328–329, 330 Augusta, Josef (1903–1968) 222–223, 331 Action comic 343 Aulocetus sammarinensis 80 Actualism, work of Capellini 82, 87 Azara, Don Felix de (1746–1821) 34, 40–41 Aepisaurus 363 Azhdarchidae 318, 319 Agassiz, Louis (1807–1873) 80, 81 Azhdarcho 319 Agustinia 380 Alexander, Annie Montague (1867–1950) 142–143, 143, Bakker, Robert. T. 145, 146 ‘dinosaur renaissance’ 375–376, 377 Alf, Karen (1954–2000), illustrator 139–140 Dinosaurian monophyly 93, 246 Algoasaurus 365 inﬂuence on graphic art 335, 343, 350 Allosaurus, digits 267, 271, 273 Bara Simla, dinosaur discoveries 164, 166–169 Allosaurus fragilis 85 Baryonyx walkeri Altispinax, pneumaticity 230–231 relation to Spinosaurus 175, 177–178, 178, 181, 183 Alum Shale Member, Parapsicephalus purdoni 195 work of Charig 94, 95, 102, 103 Amargasaurus 380 Beasley, Henry Charles (1836–1919) Amphicoelias 365, 366, 368, 370 Chirotherium 214–215, 219 amphisbaenians, work of Charig 95 environment 219–220 anatomy, comparative 23 Beaux, E. Cecilia (1855–1942), illustrator 138, 139, 146 Andrews, Roy Chapman (1884–1960) 69, 122 Becklespinax altispinax, pneumaticity 230–231, Andrews, Yvette 122 232, 363 Anning, Joseph (1796–1849) 14 belemnites, Oxford Clay Formation, Peterborough Anning, Mary (1799–1847) 24, 25, 113–116, 114, brick pits 53 145, 146, 147, 288 Benett, Etheldred (1776–1845) 117, 146 Dimorphodon macronyx 14, 115, 294 Bhattacharji, Durgansankar 166 Hawker’s ‘Crocodile’ 14 Birch, Lt.
[Show full text]
SUPPLEMENTARY INFORMATION Doi:10.1038/Nature24011
SUPPLEMENTARY INFORMATION doi:10.1038/nature24011 1. Details of the new phylogenetic analysis 1.1. Modifications to Baron et al. (2017) data matrix The following list presents all character scoring modifications to the original taxon-character matrix of Baron et al. (2017). Unless explicitly mentioned, specimen numbers without asterisks have been scored from notes and photographs after their first-hand examination by at least one of the authors, specimens marked with † were coded based only on photographic material, and specimens marked with * were coded on direct observation of the specimens. Aardonyx celestae; score modifications based on the first-hand observation of all specimens mentioned in Yates et al. (2010). 19: 0 >1. 21 0 >1. 54: 0 >?. 57: 0 >?. 156: 1 >0. 202: 1 >0. 204: 1 >0. 266: 1 >0. 280: ? >0. Ch 286: 2 >1. 348: 0 >?. 365: ? >1. 376: ? >0. 382: 0 >?. 439: 0 >1. 450: 1 >0. Abrictosaurus consors; score modifications based on NHMUK RU B54†. Further bibliographic source: Sereno (2012). 7: 0>?; 26 0>?; 35. 2>0/1; 47: 0>?; 54 1>?; 369 0>?; 424 1>?. Agilisaurus louderbacki; score modifications based on Barrett et al. (2005) and scorings in Butler et al. (2008) and Barrett et al. (2016). 6: 0>?; 11: 0>1; 35: 1>0; 54: 1>0; 189: ?>0. Agnosphitys cromhallensis; score modifications based on cast of VMNH 1751. Further bibliographic source: Fraser et al. (2001). 15: ? >0; 16: ? >0; 21: ? >1; 24: ? >1; 30: 0 >?; 159: 0 >1; 160: - >0; 164: - >?; 165: ? >0; 167: ? >0; 172: 0 >?; 176: 0 >?; 177: 1 >0; 180: ? >0; 185: 0 >?; 221: 0 >?; 222: 0 >?; 252: 0 >1; 253: 0 >1; 254: 1 >?; 256: 0 >1; 258: 1 >?; 259: ? >0; 292: ? >1; 298: ? >0; 303: 1 >2; 305: 2 >1; 306: ? >2; 315: 1 >0; 317: ? >1; 318: ? >0; 409: ? >0; 411: 1 >0; 419: 1 >0; 421: ? >0.
[Show full text]
ABSTRACT Resurrecting Tyrannosaurus Rex Lauren E. Ammerman Director: Jennifer Good, Ph.D. After the First Successful Extraction
ABSTRACT Resurrecting Tyrannosaurus rex Lauren E. Ammerman Director: Jennifer Good, Ph.D. After the first successful extraction of ancient DNA from a fossilized Quagga in 1984, the subsequent development of PCR (Polymerase Chain Reaction) technology opened up a plethora of possibilities in the field of molecular paleontology. Supplied with fragmented ancient genomes, some scientists acted as if the days of resurrecting dinosaurs were a few technical difficulties away. Theories surfaced on the possible applications of ancient DNA technology, and some, such as creating tactical dinosaurs for the U.S. military, were outrageous. A less ridiculous idea surfaced in the form of Michael Crichton’s Jurassic Park, published in 1990. Coupled with Steven Spielberg’s 1993 feature film adaption, the Jurassic Park series created a world in which genetically- engineered dinosaurs roamed once again as theme park attractions on a billionaire’s private island, and explored the possible outcomes of a “Jurassic Park” experiment. Jurassic Park ignited scientific debate over the technological feasibility, environmental impact, and ethical questions of a “Jurassic Park” experiment. This thesis continues that conversation by asking, could resurrecting a dinosaur be a productive environmental enterprise, other than a mere display of power over Nature? Focusing on Tyrannosaurus rex, this thesis combines a brief survey the current state of dinosaur genetic research, with analyses of rewilding with large predators, to discuss whether or not scientists should ever attempt to re-create a T. rex in the future. APPROVED BY DIRECTOR OF HONORS THESIS Dr. Jennifer Good, Director of University Scholars APPROVED BY THE HONORS PROGRAM Dr. Elizabeth Corey, Director DATE: RESURRECTING TYRANNOSAURUS REX A Thesis Submitted to the Faculty of Baylor University In Partial Fulfillment of the Requirements for the Honors Program By Lauren E.
[Show full text]
Body-Size Evolution in the Dinosauria
8 Body-Size Evolution in the Dinosauria Matthew T. Carrano Introduction The evolution of body size and its influence on organismal biology have received scientific attention since the earliest decades of evolutionary study (e.g., Cope, 1887, 1896; Thompson, 1917). Both paleontologists and neontologists have attempted to determine correlations between body size and numerous aspects of life history, with the ultimate goal of docu- menting both the predictive and causal connections involved (LaBarbera, 1986, 1989). These studies have generated an appreciation for the thor- oughgoing interrelationships between body size and nearly every sig- nificant facet of organismal biology, including metabolism (Lindstedt & Calder, 1981; Schmidt-Nielsen, 1984; McNab, 1989), population ecology (Damuth, 1981; Juanes, 1986; Gittleman & Purvis, 1998), locomotion (Mc- Mahon, 1975; Biewener, 1989; Alexander, 1996), and reproduction (Alex- ander, 1996). An enduring focus of these studies has been Cope’s Rule, the notion that body size tends to increase over time within lineages (Kurtén, 1953; Stanley, 1973; Polly, 1998). Such an observation has been made regarding many different clades but has been examined specifically in only a few (MacFadden, 1986; Arnold et al., 1995; Jablonski, 1996, 1997; Trammer & Kaim, 1997, 1999; Alroy, 1998). The discordant results of such analyses have underscored two points: (1) Cope’s Rule does not apply universally to all groups; and (2) even when present, size increases in different clades may reflect very different underlying processes. Thus, the question, “does Cope’s Rule exist?” is better parsed into two questions: “to which groups does Cope’s Rule apply?” and “what process is responsible for it in each?” Several recent works (McShea, 1994, 2000; Jablonski, 1997; Alroy, 1998, 2000a, 2000b) have begun to address these more specific questions, attempting to quantify patterns of body-size evolution in a phylogenetic (rather than strictly temporal) context, as well as developing methods for interpreting the resultant patterns.
[Show full text]
The Origin and Evolution of the Dinosaur Infraorder Carnosauria*
PALEONTOLOGICHESKIY ZHURNAL 1989 No. 4 KURZANOV S. M. THE ORIGIN AND EVOLUTION OF THE DINOSAUR INFRAORDER CARNOSAURIA* Paleontological Institute of the Academy of Sciences of the USSR Based on a revision of the systematic composition of the carnosaur families, a new diagram of the phylogenetic relationships within the infraorder is proposed. The question of carnosaurs cannot be considered to be resolved. Excluding the Triassic forms, carnosaurs in the broad or narrow sense have always been considered to be a group of theropods because they are only slightly different from them in fundamental features associated with large body size and a predatory lifestyle. The Late Triassic genera, such as Teratosaurus and Sinosaurus [33], were assigned to these on the basis of extremely meager material and without sufficient justification. This assignment has subsequently been rejected by most authors [13, 16, 17, 24, 25]. Huene [23] suggested that, along with the Sauropoda and Prosauropoda, the carnosaurs form a natural group Pachypodosauria, within which they are thought to be direct descendants of the prosauropods (the carnosaurs proceed directly from Teratosaurus through Magnosaurus). Studies of abundant cranial material (which actually belongs to Sellosaurus gracilis Huene) gave reason to think that the first species had been a prosauropod, whereas typical material (maxilla, ischium) belong to thecodonts from the family Poposauridae [24]. Huene’s diagram, which initially did not receive support, was widely propagated by the discovery of an unusual carnosaur Torvosaurus tanneri Galton et Jensen in the Upper Triassic deposits of Colorado [25]. The exceptionally plesiomorphic nature of some of its features, in the authors’ opinion, gave sufficient justification for removing them from the prosauropods.
[Show full text]
A Four-Legged Megalosaurus and Swimming Brontosaurs
Channels: Where Disciplines Meet Volume 2 Number 2 Spring 2018 Article 5 April 2018 A Four-Legged Megalosaurus and Swimming Brontosaurs Jordan C. Oldham Cedarville University, [email protected] Follow this and additional works at: https://digitalcommons.cedarville.edu/channels Part of the Geology Commons, History of Philosophy Commons, Paleontology Commons, and the Philosophy of Science Commons DigitalCommons@Cedarville provides a publication platform for fully open access journals, which means that all articles are available on the Internet to all users immediately upon publication. However, the opinions and sentiments expressed by the authors of articles published in our journals do not necessarily indicate the endorsement or reflect the views of DigitalCommons@Cedarville, the Centennial Library, or Cedarville University and its employees. The authors are solely responsible for the content of their work. Please address questions to [email protected]. Recommended Citation Oldham, Jordan C. (2018) "A Four-Legged Megalosaurus and Swimming Brontosaurs," Channels: Where Disciplines Meet: Vol. 2 : No. 2 , Article 5. DOI: 10.15385/jch.2018.2.2.5 Available at: https://digitalcommons.cedarville.edu/channels/vol2/iss2/5 A Four-Legged Megalosaurus and Swimming Brontosaurs Abstract Thomas Kuhn in his famous work The Structure of Scientific Revolutions laid out the framework for his theory of how science changes. At the advent of dinosaur paleontology fossil hunters like Gideon Mantell discovered some of the first dinosaurs like Iguanodon and Megalosaurus. Through new disciples like Georges Cuvier’s comparative anatomy lead early dinosaur paleontologist to reconstruct them like giant reptiles of absurd proportions. This lead to the formation of a new paradigm that prehistoric animals like dinosaurs existed and eventually went extinct.
[Show full text]
Download Your Dinosaur Timeline Sheet Here
Terms and Conditions of Use This file is for personal, classroom or public library use only. By downloading it, you agree that you will not copy or reproduce the files except for your own personal, non-commercial use. Modification of terms. I have the right to modify the terms of this Agreement at any time; the modification will be effective immediately and shall replace all prior Agreements. You may… You may NOT… •Print as many copies as you’d like to use in •Claim my files as your own. your own classroom, home or public library. •Alter my electronic files in any way. •Post online about a printable (for example— take a picture of your child or student using •Sell or in anyway profit from my electronic it), giving proper credit to Rainy Day Mum files. and must link back to the original source for •Print my files and then sell the printed downloading. copies to others. •Store or distribute my files on any other website or another location where others are able to electronically retrieve them (for ex- ample: amazon Inspire, Dropbox, 4Shared, Mediafire, Facebook groups and forums, etc.). •Email my files to anyone or transmit them in any other fashion Copyright Rainy Day Mum © 2019 © Rainy Day Mum 2019 Images by BoiArt https://www.teacherspayteachers.com/Store/Bioart © Rainy Day Mum 2019 Images by BoiArt https://www.teacherspayteachers.com/Store/Bioart © Rainy Day Mum 2019 Images by BoiArt https://www.teacherspayteachers.com/Store/Bioart Dinosaur Picture Dinosaur Name Period Plateosaurus Troodon Edmontosaurus Deinonychus Dilophasarus Carnotaurus
[Show full text]
A New Specimen of Acrocanthosaurus Atokensis (Theropoda, Dinosauria) from the Lower Cretaceous Antlers Formation (Lower Cretaceous, Aptian) of Oklahoma, USA
A new specimen of Acrocanthosaurus atokensis (Theropoda, Dinosauria) from the Lower Cretaceous Antlers Formation (Lower Cretaceous, Aptian) of Oklahoma, USA Philip J. CURRIE Royal Tyrrell Museum of Palaeontology, Box 7500, Drumheller, Alberta T0J 0Y0 (Canada) [email protected] Kenneth CARPENTER Denver Museum of Natural History, Department of Earth Sciences, City Park, Denver, Colorado 80205 (USA) [email protected] Currie P. J. & Carpenter K. 2000. — A new specimen of Acrocanthosaurus atokensis (Theropoda, Dinosauria) from the Lower Cretaceous Antlers Formation (Lower Cretaceous, Aptian) of Oklahoma, USA. Geodiversitas 22 (2) : 207-246. The data matrix is available at http://www.mnhn.fr/publication/matadd/g00n2a3.html ABSTRACT A new skeleton of Acrocanthosaurus atokensis is the most complete specimen collected and has the only known complete skull. Aspects of the new skeleton are described in detail, with special attention directed to the morphology of the skull and forelimb. Although unquestionably one of the largest theropods ever found, it is smaller than Carcharodontosaurus, Giganotosaurus and Tyrannosaurus. Comparison with other theropods suggests that Acrocanthosaurus bears a strong resemblance to these taxa because of charac- KEY WORDS ters that are size determinate, and the evidence suggests Acrocanthosaurus is Dinosaurs, more closely related to Allosauridae than to Carcharodontosauridae. Three theropods, Early Cretaceous, families (Allosauridae, Carcharodontosauridae, Sinraptoridae) are recognized USA. in the Allosauroidea. GEODIVERSITAS • 2000 • 22 (2) © Publications Scientifiques du Muséum national d’Histoire naturelle, Paris. www.mnhn.fr/publication/ 207 Currie P. J. & Carpenter K. RÉSUMÉ Un nouveau specimen d’Acrocanthosaurus atokensis (Theropoda, Dinosauria) du Crétacé inférieur de la Formation Antlers (Crétacé inférieur, Aptien) de l’Oklahoma, États-Unis.
[Show full text]
The Dentition of Megalosaurid Theropods
The dentition of megalosaurid theropods CHRISTOPHE HENDRICKX, OCTÁVIO MATEUS, and RICARDO ARAÚJO Hendrickx, C., Mateus, O., and Araújo, R. 2015. The dentition of megalosaurid theropods. Acta Palaeontologica Polo- nica 60 (3): 627–642. Theropod teeth are particularly abundant in the fossil record and frequently reported in the literature. Yet, the dentition of many theropods has not been described comprehensively, omitting details on the denticle shape, crown ornamentations and enamel texture. This paucity of information has been particularly striking in basal clades, thus making identification of isolated teeth difficult, and taxonomic assignments uncertain. We here provide a detailed description of the dentition of Megalosauridae, and a comparison to and distinction from superficially similar teeth of all major theropod clades. Megalosaurid dinosaurs are characterized by a mesial carina facing mesiolabially in mesial teeth, centrally positioned carinae on both mesial and lateral crowns, a mesial carina terminating above the cervix, and short to well-developed in- terdenticular sulci between distal denticles. A discriminant analysis performed on a dataset of numerical data collected on the teeth of 62 theropod taxa reveals that megalosaurid teeth are hardly distinguishable from other theropod clades with ziphodont dentition. This study highlights the importance of detailing anatomical descriptions and providing additional morphometric data on teeth with the purpose of helping to identify isolated theropod teeth in the future. Key words: Theropoda, Tetanurae, Megalosauridae, dentition, teeth, morphometry. Christophe Hendrickx [[email protected]] and Octávio Mateus [[email protected]], Universidade Nova de Lisboa, GeoBioTec (formerly CICEGe), Departamento de Ciências da Terra, Faculdade de Ciências e Tec- nologia, Quinta da Torre, 2829-516, Caparica, Portugal; Museu da Lourinhã, 9 Rua João Luis de Moura, 2530-158, Lourinhã, Portugal.
[Show full text]
New Information on the Cranial Anatomy of Acrocanthosaurus Atokensis and Its Implications for the Phylogeny of Allosauroidea (Dinosauria: Theropoda)
New Information on the Cranial Anatomy of Acrocanthosaurus atokensis and Its Implications for the Phylogeny of Allosauroidea (Dinosauria: Theropoda) Drew R. Eddy*¤, Julia A. Clarke¤ Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina, United States of America Abstract Background: Allosauroidea has a contentious taxonomic and systematic history. Within this group of theropod dinosaurs, considerable debate has surrounded the phylogenetic position of the large-bodied allosauroid Acrocanthosaurus atokensis from the Lower Cretaceous Antlers Formation of North America. Several prior analyses recover Acrocanthosaurus atokensis as sister taxon to the smaller-bodied Allosaurus fragilis known from North America and Europe, and others nest Acrocanthosaurus atokensis within Carcharodontosauridae, a large-bodied group of allosauroids that attained a cosmopolitan distribution during the Early Cretaceous. Methodology/Principal Findings: Re-evaluation of a well-preserved skull of Acrocanthosaurus atokensis (NCSM 14345) provides new information regarding the palatal complex and inner surfaces of the skull and mandible. Previously inaccessible internal views and articular surfaces of nearly every element of the skull are described. Twenty-four new morphological characters are identified as variable in Allosauroidea, combined with 153 previously published characters, and evaluated for eighteen terminal taxa. Systematic analysis of this dataset recovers a single most parsimonious topology placing Acrocanthosaurus atokensis as a member of Allosauroidea, in agreement with several recent analyses that nest the taxon well within Carcharodontosauridae. Conclusions/Significance: A revised diagnosis of Acrocanthosaurus atokensis finds that the species is distinguished by four primary characters, including: presence of a knob on the lateral surangular shelf; enlarged posterior surangular foramen; supraoccipital protruding as a double-boss posterior to the nuchal crest; and pneumatic recess within the medial surface of the quadrate.
[Show full text]