1
|
Zanno LE, Gates TA, Avrahami HM, Tucker RT, Makovicky PJ. An early-diverging iguanodontian (Dinosauria: Rhabdodontomorpha) from the Late Cretaceous of North America. PLoS One 2023; 18:e0286042. [PMID: 37285376 DOI: 10.1371/journal.pone.0286042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 05/08/2023] [Indexed: 06/09/2023] Open
Abstract
Intensifying macrovertebrate reconnaissance together with refined age-dating of mid-Cretaceous assemblages in recent decades is producing a more nuanced understanding of the impact of the Cretaceous Thermal Maximum on terrestrial ecosystems. Here we report discovery of a new early-diverging ornithopod, Iani smithi gen. et sp. nov., from the Cenomanian-age lower Mussentuchit Member, Cedar Mountain Formation of Utah, USA. The single known specimen of this species (NCSM 29373) includes a well-preserved, disarticulated skull, partial axial column, and portions of the appendicular skeleton. Apomorphic traits are concentrated on the frontal, squamosal, braincase, and premaxilla, including the presence of three premaxillary teeth. Phylogenetic analyses using parsimony and Bayesian inference posit Iani as a North American rhabdodontomorph based on the presence of enlarged, spatulate teeth bearing up to 12 secondary ridges, maxillary teeth lacking a primary ridge, a laterally depressed maxillary process of the jugal, and a posttemporal foramen restricted to the squamosal, among other features. Prior to this discovery, neornithischian paleobiodiversity in the Mussentuchit Member was based primarily on isolated teeth, with only the hadrosauroid Eolambia caroljonesa named from macrovertebrate remains. Documentation of a possible rhabdodontomorph in this assemblage, along with published reports of an as-of-yet undescribed thescelosaurid, and fragmentary remains of ankylosaurians and ceratopsians confirms a minimum of five, cohabiting neornithischian clades in earliest Late Cretaceous terrestrial ecosystems of North America. Due to poor preservation and exploration of Turonian-Santonian assemblages, the timing of rhabdodontomorph extirpation in the Western Interior Basin is, as of yet, unclear. However, Iani documents survival of all three major clades of Early Cretaceous neornithischians (Thescelosauridae, Rhabdodontomorpha, and Ankylopollexia) into the dawn of the Late Cretaceous of North America.
Collapse
Affiliation(s)
- Lindsay E Zanno
- Paleontology, North Carolina Museum of Natural Sciences, Raleigh, North Carolina, United States of America
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Terry A Gates
- Paleontology, North Carolina Museum of Natural Sciences, Raleigh, North Carolina, United States of America
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Haviv M Avrahami
- Paleontology, North Carolina Museum of Natural Sciences, Raleigh, North Carolina, United States of America
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Ryan T Tucker
- Department of Earth Sciences, Stellenbosch University, Stellenbosch, South Africa
| | - Peter J Makovicky
- Department of Earth and Environmental Sciences, University of Minnesota, Minneapolis, Minnesota, United States of America
| |
Collapse
|
2
|
Rotatori FM, Moreno-Azanza M, Mateus O. Reappraisal and new material of the holotype of Draconyx loureiroi (Ornithischia: Iguanodontia) provide insights on the tempo and modo of evolution of thumb-spiked dinosaurs. Zool J Linn Soc 2022. [DOI: 10.1093/zoolinnean/zlab113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
The Upper Jurassic Lourinhã Formation is well known for its rich assemblage of fossil vertebrates. In this formation, ornithopod dinosaurs are represented by two iguanodontian species, Eousdryosaurus nanohallucis and Draconyx loureiroi. We recently became aware of unreported material belonging to the holotype of Draconyx loureiroi, consisting of partially articulated manual elements. We here re-describe the holotype specimen ML 357, including the newly discovered material. The specimen was subjected to CT-scanning and its surface data used to assess anatomical characters. Linear measurements of metatarsal III were used to estimate the body length of the specimen. The Draconyx loureiroi holotype was included in two datasets and analysed with maximum parsimony and Bayesian inference approaches to estimate evolutionary rates among Iguanodontia. We present evidence that Draconyx loureiroi is a valid taxon nested in Styracosterna and is clearly diagnosable by a unique combination of characters. Both maximum parsimony and Bayesian inference indicate high evolutionary rates across the Jurassic/Cretaceous transition for the base of Iguanodontia. Length estimation suggests that Draconyx loureiroi was a relatively small, bipedal and possibly cursorial animal. Given its basal phyletic position, we interpret this bauplan was the ancestral condition for Styracosterna, that only later in the Cretaceous evolved into giant quadrupedal forms.
Collapse
Affiliation(s)
- Filippo Maria Rotatori
- GEOBIOTEC, Department of Earth Sciences, NOVA School of Science and Technology, Campus de Caparica, P-2829 516 Caparica, Portugal
- Museu da Lourinhã, Rua João Luis de Moura 95, 2530-158, Lourinhã, Portugal
| | - Miguel Moreno-Azanza
- GEOBIOTEC, Department of Earth Sciences, NOVA School of Science and Technology, Campus de Caparica, P-2829 516 Caparica, Portugal
- Museu da Lourinhã, Rua João Luis de Moura 95, 2530-158, Lourinhã, Portugal
- Grupo Aragosaurus-IUCA, Facultad de Ciencias, Universidad de Zaragoza, 50009, Zaragoza, Spain
| | - Octávio Mateus
- GEOBIOTEC, Department of Earth Sciences, NOVA School of Science and Technology, Campus de Caparica, P-2829 516 Caparica, Portugal
- Museu da Lourinhã, Rua João Luis de Moura 95, 2530-158, Lourinhã, Portugal
| |
Collapse
|
3
|
New Iguanodon bernissartensis Axial Bones (Dinosauria, Ornithopoda) from the Early Cretaceous of Morella, Spain. DIVERSITY 2022. [DOI: 10.3390/d14020063] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Iguanodon bernissartensis is the most frequently and widely cited styracosternan ornithopod in Western Europe during the Early Cretaceous, although some of these assignments likely need to be revised to establish the true distribution of the taxon. Here, we describe a new specimen of I. bernissartensis from the upper Barremian of the Iberian Peninsula. Based on the unique combination of shared characters, the new specimen from the Arcillas de Morella Formation at Morella locality (Castellón, Spain) can be confidently referred to Iguanodon bernissartensis. These characters include parallel-sided anterior and posterior margins of the dorsal and the caudal neural spines as well as the presence of a ventral keel in the posterior dorsal centra and a broad ventral sulcus in the midline of the central surface of the most posterior sacral vertebrae. This new evidence of Iguanodon bernissartensis reinforces the knowledge about styracosternan ornithopods as the most frequently recorded dinosaur group in the Arcillas de Morella Formation.
Collapse
|
4
|
Madzia D, Arbour VM, Boyd CA, Farke AA, Cruzado-Caballero P, Evans DC. The phylogenetic nomenclature of ornithischian dinosaurs. PeerJ 2021; 9:e12362. [PMID: 34966571 PMCID: PMC8667728 DOI: 10.7717/peerj.12362] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 09/30/2021] [Indexed: 11/25/2022] Open
Abstract
Ornithischians form a large clade of globally distributed Mesozoic dinosaurs, and represent one of their three major radiations. Throughout their evolutionary history, exceeding 134 million years, ornithischians evolved considerable morphological disparity, expressed especially through the cranial and osteodermal features of their most distinguishable representatives. The nearly two-century-long research history on ornithischians has resulted in the recognition of numerous diverse lineages, many of which have been named. Following the formative publications establishing the theoretical foundation of phylogenetic nomenclature throughout the 1980s and 1990s, many of the proposed names of ornithischian clades were provided with phylogenetic definitions. Some of these definitions have proven useful and have not been changed, beyond the way they were formulated, since their introduction. Some names, however, have multiple definitions, making their application ambiguous. Recent implementation of the International Code of Phylogenetic Nomenclature (ICPN, or PhyloCode) offers the opportunity to explore the utility of previously proposed definitions of established taxon names. Since the Articles of the ICPN are not to be applied retroactively, all phylogenetic definitions published prior to its implementation remain informal (and ineffective) in the light of the Code. Here, we revise the nomenclature of ornithischian dinosaur clades; we revisit 76 preexisting ornithischian clade names, review their recent and historical use, and formally establish their phylogenetic definitions. Additionally, we introduce five new clade names: two for robustly supported clades of later-diverging hadrosaurids and ceratopsians, one uniting heterodontosaurids and genasaurs, and two for clades of nodosaurids. Our study marks a key step towards a formal phylogenetic nomenclature of ornithischian dinosaurs.
Collapse
Affiliation(s)
- Daniel Madzia
- Department of Evolutionary Paleobiology, Institute of Paleobiology, Polish Academy of Sciences, Warsaw, Poland
| | - Victoria M. Arbour
- Department of Knowledge, Royal BC Museum, Victoria, BC, Canada
- School of Earth and Ocean Sciences, University of Victoria, Victoria, BC, Canada
| | | | - Andrew A. Farke
- Raymond M. Alf Museum of Paleontology at The Webb Schools, Claremont, CA, USA
| | - Penélope Cruzado-Caballero
- Área de Paleontología, Departamento de Biología Animal, Edafología y Geología, Universidad de La Laguna, Santa Cruz de Tenerife, Spain
- Instituto de Investigación en Paleobiología y Geología (IIPG), Universidad Nacional de Río Negro (UNRN), Río Negro, Argentina
- Instituto de Investigación en Paleobiología y Geología (IIPG), Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Río Negro, Argentina
- Grupo Aragosaurus-IUCA, Área de Paleontología, Departamento de Ciencias de la Tierra, Universidad de Zaragoza, Zaragoza, Spain
| | - David C. Evans
- Department of Natural History, Royal Ontario Museum, Toronto, ON, Canada
| |
Collapse
|
5
|
Chiarenza AA, Fabbri M, Consorti L, Muscioni M, Evans DC, Cantalapiedra JL, Fanti F. An Italian dinosaur Lagerstätte reveals the tempo and mode of hadrosauriform body size evolution. Sci Rep 2021; 11:23295. [PMID: 34857789 PMCID: PMC8640049 DOI: 10.1038/s41598-021-02490-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 11/17/2021] [Indexed: 02/07/2023] Open
Abstract
During the latest Cretaceous, the European Archipelago was characterized by highly fragmented landmasses hosting putative dwarfed, insular dinosaurs, claimed as fossil evidence of the “island rule”. The Villaggio del Pescatore quarry (north-eastern Italy) stands as the most informative locality within the palaeo-Mediterranean region and represents the first, multi-individual Konservat-Lagerstätte type dinosaur-bearing locality in Italy. The site is here critically re-evaluated as early Campanian in age, thus preceding the final fragmentation stages of the European Archipelago, including all other European localities preserving hypothesized dwarfed taxa. New skeletal remains allowed osteohistological analyses on the hadrosauroid Tethyshadros insularis indicating subadult features in the type specimen whereas a second, herein newly described, larger individual is likely somatically mature. A phylogenetic comparative framework places the body-size of T. insularis in range with other non-hadrosaurid Eurasian hadrosauroids, rejecting any significant evolutionary trend towards miniaturisation in this clade, confuting its ‘pygmy’ status, and providing unmatched data to infer environmentally-driven body-size trends in Mesozoic dinosaurs.
Collapse
Affiliation(s)
| | - Matteo Fabbri
- Field Museum of Natural History, Chicago, IL, 60605, USA
| | - Lorenzo Consorti
- Department of Mathematics and Geosciences, University of Trieste, 34128, Trieste, Italy.,Geological Survey of Italy (ISPRA), 00144, Rome, Italy
| | - Marco Muscioni
- Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Alma Mater Studiorum, Università Di Bologna, 40126, Bologna, Italy
| | - David C Evans
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, M5S 3B2, Canada.,Department of Natural History, Royal Ontario Museum, Toronto, ON, M5S 2C6, Canada
| | - Juan L Cantalapiedra
- GloCEE-Global Change Ecology and Evolution Research Group, Departamento de Ciencias de la Vida, Universidad de Alcalá, 28801, Alcalá de Henares, Spain
| | - Federico Fanti
- Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Alma Mater Studiorum, Università Di Bologna, 40126, Bologna, Italy
| |
Collapse
|
6
|
Santos-Cubedo A, de Santisteban C, Poza B, Meseguer S. A new styracosternan hadrosauroid (Dinosauria: Ornithischia) from the Early Cretaceous of Portell, Spain. PLoS One 2021; 16:e0253599. [PMID: 34232957 PMCID: PMC8262792 DOI: 10.1371/journal.pone.0253599] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 06/08/2021] [Indexed: 11/18/2022] Open
Abstract
A new styracosternan ornithopod genus and species is described based on the right dentary of a single specimen from the Mirambell Formation (Early Cretaceous, early Barremian) at the locality of Portell, (Castellón, Spain). Portellsaurus sosbaynati gen. et sp. nov. is diagnosed by two autapomorphic features as well as a unique combination of characters. The autapomorphies include: the absence of a bulge along the ventral margin directly ventral to the base of the coronoid process and the presence of a deep oval cavity on the medial surface of the mandibular adductor fossa below the eleventh-twelfth tooth position. Phylogenetic analyses reveal that the new Iberian form is more closely related to the African taxon Ouranosaurus nigeriensis than to its synchronic Iberian taxa Magnamanus soriaensis and Iguanodon galvensis. In addition, Portellsaurus sosbaynati is less related to other Iberian taxa such as Iguanodon bernissartensis and Proa valdearinnoensis than to the other Early Cretaceous Iberian styracosternans Mantellisaurus atherfieldensis and Morelladon beltrani. A new phylogenetic hypothesis is proposed that resolves Iguanodon (I. bernissartensis, I. galvensis) with the Valanginian Barilium dawsoni into a monophyletic clade (Iguanodontoidea). The recognition of Portellsaurus sosbaynati gen. et sp. nov. as the first styracosternan dinosaur species identified from the Margas de Mirambell Formation (early Barremian-early late Barremian) in the Morella sub-basin (Maestrat Basin, eastern Spain) indicates that the Iberian Peninsula was home to a highly diverse assemblage of medium-to-large bodied styracosternan hadrosauriforms during the Early Cretaceous.
Collapse
Affiliation(s)
- Andrés Santos-Cubedo
- Àrea de Cristal·lografia i Mineralogia, Departament de Ciències Agràries i del Medi Natural, Universitat Jaume I, Castelló, España
- Grup Guix, Vila-real, Castelló, España
| | - Carlos de Santisteban
- Departament de Botànica i Geologia, Universitat de València, Burjassot, València, España
| | | | - Sergi Meseguer
- Àrea de Cristal·lografia i Mineralogia, Departament de Ciències Agràries i del Medi Natural, Universitat Jaume I, Castelló, España
| |
Collapse
|
7
|
Schroeder K, Lyons SK, Smith FA. The influence of juvenile dinosaurs on community structure and diversity. Science 2021; 371:941-944. [PMID: 33632845 DOI: 10.1126/science.abd9220] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 01/21/2021] [Indexed: 12/15/2022]
Abstract
Despite dominating biodiversity in the Mesozoic, dinosaurs were not speciose. Oviparity constrained even gigantic dinosaurs to less than 15 kg at birth; growth through multiple morphologies led to the consumption of different resources at each stage. Such disparity between neonates and adults could have influenced the structure and diversity of dinosaur communities. Here, we quantified this effect for 43 communities across 136 million years and seven continents. We found that megatheropods (more than 1000 kg) such as tyrannosaurs had specific effects on dinosaur community structure. Although herbivores spanned the body size range, communities with megatheropods lacked carnivores weighing 100 to 1000 kg. We demonstrate that juvenile megatheropods likely filled the mesocarnivore niche, resulting in reduced overall taxonomic diversity. The consistency of this pattern suggests that ontogenetic niche shift was an important factor in generating dinosaur community structure and diversity.
Collapse
Affiliation(s)
- Katlin Schroeder
- Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA.
| | - S Kathleen Lyons
- School of Biological Sciences, University of Nebraska, Lincoln, NE 68588, USA
| | - Felisa A Smith
- Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA
| |
Collapse
|
8
|
Griffin CT, Stocker MR, Colleary C, Stefanic CM, Lessner EJ, Riegler M, Formoso K, Koeller K, Nesbitt SJ. Assessing ontogenetic maturity in extinct saurian reptiles. Biol Rev Camb Philos Soc 2020; 96:470-525. [PMID: 33289322 DOI: 10.1111/brv.12666] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 10/09/2020] [Accepted: 10/28/2020] [Indexed: 01/06/2023]
Abstract
Morphology forms the most fundamental level of data in vertebrate palaeontology because it is through interpretations of morphology that taxa are identified, creating the basis for broad evolutionary and palaeobiological hypotheses. Assessing maturity is one of the most basic aspects of morphological interpretation and provides the means to study the evolution of ontogenetic changes, population structure and palaeoecology, life-history strategies, and heterochrony along evolutionary lineages that would otherwise be lost to time. Saurian reptiles (the least-inclusive clade containing Lepidosauria and Archosauria) have remained an incredibly diverse, numerous, and disparate clade through their ~260-million-year history. Because of the great disparity in this group, assessing maturity of saurian reptiles is difficult, fraught with methodological and terminological ambiguity. We compiled a novel database of literature, assembling >900 individual instances of saurian maturity assessment, to examine critically how saurian maturity has been diagnosed. We review the often inexact and inconsistent terminology used in saurian maturity assessment (e.g. 'juvenile', 'mature') and provide routes for better clarity and cross-study coherence. We describe the various methods that have been used to assess maturity in every major saurian group, integrating data from both extant and extinct taxa to give a full account of the current state of the field and providing method-specific pitfalls, best practices, and fruitful directions for future research. We recommend that a new standard subsection, 'Ontogenetic Assessment', be added to the Systematic Palaeontology portions of descriptive studies to provide explicit ontogenetic diagnoses with clear criteria. Because the utility of different ontogenetic criteria is highly subclade dependent among saurians, even for widely used methods (e.g. neurocentral suture fusion), we recommend that phylogenetic context, preferably in the form of a phylogenetic bracket, be used to justify the use of a maturity assessment method. Different methods should be used in conjunction as independent lines of evidence when assessing maturity, instead of an ontogenetic diagnosis resting entirely on a single criterion, which is common in the literature. Critically, there is a need for data from extant taxa with well-represented growth series to be integrated with the fossil record to ground maturity assessments of extinct taxa in well-constrained, empirically tested methods.
Collapse
Affiliation(s)
- Christopher T Griffin
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
| | - Michelle R Stocker
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
| | - Caitlin Colleary
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
- Department of Vertebrate Paleontology, Cleveland Museum of Natural History, 1 Wade Oval Drive, Cleveland, OH, 44106, U.S.A
| | - Candice M Stefanic
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
- Department of Anatomical Sciences, Stony Brook University, 100 Nicolls Road, Stony Brook, NY, 11794, U.S.A
| | - Emily J Lessner
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
- Department of Pathology and Anatomical Sciences, University of Missouri, 1 Hospital Drive, Columbia, MO, 65212, U.S.A
| | - Mitchell Riegler
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
- Department of Geological Sciences, University of Florida, 241 Williamson Hall, Gainesville, FL, 32611, U.S.A
| | - Kiersten Formoso
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
- Department of Earth Sciences, University of Southern California, 3651 Trousdale Pkwy, Los Angeles, CA, 90089, U.S.A
- Dinosaur Institute, Natural History Museum of Los Angeles County, 900 W Exposition Boulevard, Los Angeles, CA, 90007, U.S.A
| | - Krista Koeller
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
- Department of Biology, University of Florida, 220 Bartram Hall, Gainesville, FL, 32611, U.S.A
| | - Sterling J Nesbitt
- Department of Geosciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA, 24061, U.S.A
| |
Collapse
|
9
|
Yang Y, Wu W, Dieudonné PE, Godefroit P. A new basal ornithopod dinosaur from the Lower Cretaceous of China. PeerJ 2020; 8:e9832. [PMID: 33194351 PMCID: PMC7485509 DOI: 10.7717/peerj.9832] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 08/07/2020] [Indexed: 11/29/2022] Open
Abstract
A new basal ornithopod dinosaur, based on two nearly complete articulated skeletons, is reported from the Lujiatun Beds (Yixian Fm, Lower Cretaceous) of western Liaoning Province (China). Some of the diagnostic features of Changmiania liaoningensis nov. gen., nov. sp. are tentatively interpreted as adaptations to a fossorial behavior, including: fused premaxillae; nasal laterally expanded, overhanging the maxilla; shortened neck formed by only six cervical vertebrae; neural spines of the sacral vertebrae completely fused together, forming a craniocaudally-elongated continuous bar; fused scapulocoracoid with prominent scapular spine; and paired ilia symmetrically inclined dorsomedially, partially covering the sacrum in dorsal view. A phylogenetic analysis places Changmiania liaoningensis as the most basal ornithopod dinosaur described so far. It is tentatively hypothesized that both Changmiania liaoningensis specimens were suddenly entrapped in a collapsed underground burrow while they were resting, which would explain their perfect lifelike postures and the complete absence of weathering and scavenging traces. However, further behavioural inference remains problematic, because those specimens lack extensive sedimentological and taphonomic data, as it is also the case for most specimens collected in the Lujiatun Beds so far.
Collapse
Affiliation(s)
- Yuqing Yang
- College of Resources and Civil Engineering, Northeastern University, Shenyang, Liaoning, China.,College of Paleontology, Shenyang Normal University, Shenyang, Liaoning, China.,Key Laboratory for Evolution of Past Life and Change of Environment, Province of Liaoning, Shenyang Normal University, Shenyang, Liaoning, China
| | - Wenhao Wu
- Key Laboratory for Evolution of Past Life and Environment in Northeast Asia, Ministry of Education, Jilin University, Changchun, Jilin, China.,Research Center of Paleontology and Stratigraphy, Jilin University, Changchun, Jilin, China
| | - Paul-Emile Dieudonné
- Instituto de Investigación en Paleobiología y Geología, CONICET, Universidad Nacional de Río Negro, Rio Negro, Argentina
| | - Pascal Godefroit
- Directorate 'Earth and History of Life', Royal Belgian Institute of Natural Sciences, Brussels, Belgium
| |
Collapse
|
10
|
Li Y, Ruta M, Wills MA. Craniodental and Postcranial Characters of Non-Avian Dinosauria Often Imply Different Trees. Syst Biol 2020; 69:638-659. [PMID: 31769837 PMCID: PMC7302058 DOI: 10.1093/sysbio/syz077] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 11/08/2019] [Accepted: 11/18/2019] [Indexed: 12/28/2022] Open
Abstract
Despite the increasing importance of molecular sequence data, morphology still makes an important contribution to resolving the phylogeny of many groups, and is the only source of data for most fossils. Most systematists sample morphological characters as broadly as possible on the principle of total evidence. However, it is not uncommon for sampling to be focused on particular aspects of anatomy, either because characters therein are believed to be more informative, or because preservation biases restrict what is available. Empirically, the optimal trees from partitions of morphological data sets often represent significantly different hypotheses of relationships. Previous work on hard-part versus soft-part characters across animal phyla revealed significant differences in about a half of sampled studies. Similarly, studies of the craniodental versus postcranial characters of vertebrates revealed significantly different trees in about one-third of cases, with the highest rates observed in non-avian dinosaurs. We test whether this is a generality here with a much larger sample of 81 published data matrices across all major dinosaur groups. Using the incongruence length difference test and two variants of the incongruence relationship difference test, we found significant incongruence in about 50% of cases. Incongruence is not uniformly distributed across major dinosaur clades, being highest (63%) in Theropoda and lowest (25%) in Thyreophora. As in previous studies, our partition tests show some sensitivity to matrix dimensions and the amount and distribution of missing entries. Levels of homoplasy and retained synapomorphy are similar between partitions, such that incongruence must partly reflect differences in patterns of homoplasy between partitions, which may itself be a function of modularity and mosaic evolution. Finally, we implement new tests to determine which partition yields trees most similar to those from the entire matrix. Despite no bias across dinosaurs overall, there are striking differences between major groups. The craniodental characters of Ornithischia and the postcranial characters of Saurischia yield trees most similar to the "total evidence" trees derived from the entire matrix. Trees from these same character partitions also tend to be most stratigraphically congruent: a mutual consilience suggesting that those partitions yield more accurate trees. [Dinosauria; homoplasy; partition homogeneity.].
Collapse
Affiliation(s)
- Yimeng Li
- Department of Biology & Biochemistry, The Milner Centre for Evolution, The University of Bath, The Avenue, Claverton Down, Bath BA2 7AY, UK
| | - Marcello Ruta
- School of Life Sciences, University of Lincoln, Joseph Banks Laboratories, Green Lane, Lincoln LN6 7DL, UK
| | - Matthew A Wills
- Department of Biology & Biochemistry, The Milner Centre for Evolution, The University of Bath, The Avenue, Claverton Down, Bath BA2 7AY, UK
| |
Collapse
|
11
|
A new hadrosauroid (Dinosauria: Ornithopoda) from the Late Cretaceous Baynshire Formation of the Gobi Desert (Mongolia). PLoS One 2019; 14:e0208480. [PMID: 30995236 PMCID: PMC6469754 DOI: 10.1371/journal.pone.0208480] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2017] [Accepted: 11/16/2018] [Indexed: 11/19/2022] Open
Abstract
A new genus and species of non-hadrosaurid hadrosauroid, Gobihadros mongoliensis, is described from a virtually complete and undeformed skull and postcranial skeleton, as well as extensive referred material, collected from the Baynshire Formation (Cenomanian-Santonian) of the central and eastern Gobi Desert, Mongolia. Gobihadros mongoliensis is the first non-hadrosaurid hadrosauroid from the Late Cretaceous of central Asia known from a complete, articulated skull and skeleton. The material reveals the skeletal anatomy of a proximate sister taxon to Hadrosauridae in remarkable detail. Gobihadros is similar to Bactrosaurus johnsoni and Gilmoreosaurus mongoliensis, but can be distinguished from them in several autapomorphic traits, including the maximum number (three) of functional dentary teeth per tooth position, a premaxillary oral margin with a ‘double-layer morphology’, and a sigmoidal dorsal outline of the ilium with a well-developed, fan-shaped posterior process. All of these characters in Gobihadros are inferred to be convergent in Hadrosauridae. Phylogenetic analysis positions Gobihadros mongoliensis as a Bactrosaurus-grade hadrosauromorph hadrosauroid. Its relationship with Maastrichtian hadrosaurids from Asia (e.g., Saurolophus angustirostris, Kerberosaurus manakini, Wulagasaurus dongi, Kundurosaurus nagornyi) are sufficiently distant to indicate that these latter taxa owe their distribution to migration from North America across Beringia, rather than having a common Asian origin with Go. mongoliensis.
Collapse
|
12
|
Fondevilla V, Dalla Vecchia FM, Gaete R, Galobart À, Moncunill-Solé B, Köhler M. Ontogeny and taxonomy of the hadrosaur (Dinosauria, Ornithopoda) remains from Basturs Poble bonebed (late early Maastrichtian, Tremp Syncline, Spain). PLoS One 2018; 13:e0206287. [PMID: 30379888 PMCID: PMC6209292 DOI: 10.1371/journal.pone.0206287] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 10/09/2018] [Indexed: 11/18/2022] Open
Abstract
The lower Maastrichtian site of Basturs Poble (southern Pyrenees, Spain) is the first hadrosaur bonebed reported from Europe. It is an accumulation of disarticulated lambeosaurine skeletal elements, possibly belonging to Pararhabdodon isonensis. The sample shows high intraspecific morphological variability among many skeletal elements, suggesting the need for caution in choosing characters for phylogenetic analyses. Juvenile to adult individuals are represented in the sample, while hatchling remains are absent. Bone histology reveals that juveniles are over-represented and that the youngest individuals represented by tibia specimens were two years old. Adult individuals, with tibiae 550-600 mm long, were 14-15 years old when they died. However, individual variation in tibia length at skeletal maturity occurs within the sample, so individual maturity cannot be assumed on the basis of bone size alone. The Basturs Poble bonebed occurs within the upper part of the C31r magnetochron. Thus, lambeosaurine hadrosaurids were already present and abundant in the Ibero-Armorica Island at the end of the early Maastrichtian and P. isonensis spans the upper part of the lower Maastrichtian to the upper part of the upper Maastrichtian (upper part of C31r-lower part of C29r).
Collapse
Affiliation(s)
- Víctor Fondevilla
- Institut Català de Paleontologia Miquel Crusafont, Sabadell, Catalonia, Spain
- Departament de Geologia, Universitat Autònoma de Barcelona, Bellaterra, Catalonia, Spain
- * E-mail: ,
| | - Fabio Marco Dalla Vecchia
- Institut Català de Paleontologia Miquel Crusafont, Sabadell, Catalonia, Spain
- Museo Friulano di Storia Naturale, Udine, Italy
| | - Rodrigo Gaete
- Museu de la Conca Dellà, Isona (Lleida), Catalonia, Spain
| | - Àngel Galobart
- Institut Català de Paleontologia Miquel Crusafont, Sabadell, Catalonia, Spain
- Museu de la Conca Dellà, Isona (Lleida), Catalonia, Spain
| | - Blanca Moncunill-Solé
- Institut Català de Paleontologia Miquel Crusafont, Sabadell, Catalonia, Spain
- Departament de Biologia Animal i Vegetal, Universitat Autònoma de Barcelona, Bellaterra, Catalonia, Spain
| | - Meike Köhler
- Institut Català de Paleontologia Miquel Crusafont, Sabadell, Catalonia, Spain
- Institució Catalana de Recerca i Estudis Avançats ICREA, Barcelona, Catalonia, Spain
| |
Collapse
|
13
|
Gates TA, Tsogtbaatar K, Zanno LE, Chinzorig T, Watabe M. A new iguanodontian (Dinosauria: Ornithopoda) from the Early Cretaceous of Mongolia. PeerJ 2018; 6:e5300. [PMID: 30083450 PMCID: PMC6078070 DOI: 10.7717/peerj.5300] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 07/03/2018] [Indexed: 11/20/2022] Open
Abstract
We describe a new iguanodontian ornithopod, Choyrodon barsboldi gen. et sp. nov. from the Albian-aged Khuren Dukh Formation of Mongolia based on several partial skeletons interpreted to represent a subadult growth stage based on osteohistological features. This new taxon is diagnosed by many autapomorphies of the maxilla, nasal, lacrimal, opisthotic, predentary, and surangular. Choyrodon displays an unusual combination of traits, possessing an open antorbital fenestra (a primitive ornithopod trait) together with derived features such as a downturned dentary and enlarged narial fenestra. Histological imaging suggests that the type specimen of Choyrodon would have been a subadult at the time of death. Phylogenetic analysis of two different character matrices do not posit Choyrodon to be the sister taxon or to be more primitive than the iguanodontian Altirhinus kurzanovi, which is found in the same formation. The only resolved relationship of this new taxon is that it was hypothesized to be a sister-taxon with the North American species Eolambia caroljonesa. Though discovered in the same formation and Choyrodon being smaller-bodied than Altirhinus, it does not appear that the former species is an ontogimorph of the latter. Differences in morphology and results of the phylogenetic analyses support their distinction although more specimens of both species will allow better refinement of their uniqueness.
Collapse
Affiliation(s)
- Terry A Gates
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA.,Paleontology Unit, North Carolina Museum of Natural Sciences, Raleigh, NC, USA
| | - Khishigjav Tsogtbaatar
- Department of Paleontology, Institute of Paleontology and Geology, Mongolian Academy of Sciences, Ulaanbataar, Mongolia
| | - Lindsay E Zanno
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA.,Paleontology Unit, North Carolina Museum of Natural Sciences, Raleigh, NC, USA
| | - Tsogtbaatar Chinzorig
- Department of Paleontology, Institute of Paleontology and Geology, Mongolian Academy of Sciences, Ulaanbataar, Mongolia.,Department of Natural History and Earth Sciences, Faculty of Sciences, Hokkaido University, Hokkaido University Museum, Sapporo, Japan
| | - Mahito Watabe
- School of International Liberal Studies, Waseda University, Tokyo, Japan
| |
Collapse
|
14
|
Xu X, Tan Q, Gao Y, Bao Z, Yin Z, Guo B, Wang J, Tan L, Zhang Y, Xing H. A large-sized basal ankylopollexian from East Asia, shedding light on early biogeographic history of Iguanodontia. Sci Bull (Beijing) 2018; 63:556-563. [PMID: 36658842 DOI: 10.1016/j.scib.2018.03.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 03/21/2018] [Accepted: 03/21/2018] [Indexed: 01/21/2023]
Abstract
A presumably mostly quadrupedal ankylopollexian iguanodontian, Bayannurosaurus perfectus gen. et sp. nov., is reported here, and is represented by an excellently well-preserved skeleton from the Lower Cretaceous Bayingebi Formation of Inner Mongolia, China. The diagnosis of the taxon includes several autapomorphies, notably a dorsally directed, strap-like posterodorsal process of the jugal and a horizontally oriented preacetabular process of the ilium. The nearly complete caudal series retains eight posterior-most caudals with procoelous, trapezoidal centra in dorsal view, and the last three caudals are fully fused. The discovery of B. perfectus opens a critical new window on the early evolution and intercontinental dispersal of Iguanodontia. The skeleton displays a transitional morphology between non-hadrosauriform ankylopollexians and Hadrosauriformes. A phylogenetic analysis indicates that Bayannurosaurus is positioned higher on the tree than Hypselospinus, but below Ouranosaurus just outside of Hadrosauriformes. The tree topology of Iguanodontia with temporal and spatial constraints reveals a possible biogeographic scenario supported by the statistical dispersal-vicariance analysis: around the J/K boundary, non-hadrosauriform ankylopollexians experienced multiple dispersal events from Europe to Asia, accompanying the coeval fall of the global sea level.
Collapse
Affiliation(s)
- Xing Xu
- Key Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China.
| | - Qingwei Tan
- Long Hao Institute of Geology and Paleontology, Hohhot 010010, China
| | - Yilong Gao
- Bureau of Land and Resources of Bayannur, Bayannur 015000, China
| | - Zhiqiang Bao
- Bureau of Land and Resources of Bayannur, Bayannur 015000, China
| | - Zhigang Yin
- Bureau of Land and Resources of Bayannur, Bayannur 015000, China
| | - Bin Guo
- Bureau of Land and Resources of Bayannur, Bayannur 015000, China
| | - Junyou Wang
- Inner Mongolia Museum of Natural History, Hohhot 010020, China
| | - Lin Tan
- Long Hao Institute of Geology and Paleontology, Hohhot 010010, China
| | - Yuguang Zhang
- Beijing Museum of Natural History, Beijing Academy of Science and Technology, Beijing 100050, China
| | - Hai Xing
- Beijing Museum of Natural History, Beijing Academy of Science and Technology, Beijing 100050, China.
| |
Collapse
|
15
|
Bertozzo F, Dalla Vecchia FM, Fabbri M. The Venice specimen of Ouranosaurus nigeriensis (Dinosauria, Ornithopoda). PeerJ 2017. [PMID: 28649466 PMCID: PMC5480399 DOI: 10.7717/peerj.3403] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ouranosaurus nigeriensis is an iconic African dinosaur taxon that has been described on the basis of two nearly complete skeletons from the Lower Cretaceous Gadoufaoua locality of the Ténéré desert in Niger. The entire holotype and a few bones attributed to the paratype formed the basis of the original description by Taquet (1976). A mounted skeleton that appears to correspond to O. nigeriensis has been on public display since 1975, exhibited at the Natural History Museum of Venice. It was never explicitly reported whether the Venice specimen represents a paratype and therefore, the second nearly complete skeleton reported in literature or a third unreported skeleton. The purpose of this paper is to disentangle the complex history of the various skeletal remains that have been attributed to Ouranosaurus nigeriensis (aided by an unpublished field map of the paratype) and to describe in detail the osteology of the Venice skeleton. The latter includes the paratype material (found in 1970 and collected in 1972), with the exception of the left femur, the right coracoid and one manus ungual phalanx I, which were replaced with plaster copies, and (possibly) other manus phalanges. Some other elements (e.g., the first two chevrons, the right femur, the right tibia, two dorsal vertebrae and some pelvic bones) were likely added from other individual/s. The vertebral column of the paratype was articulated and provides a better reference for the vertebral count of this taxon than the holotype. Several anatomical differences are observed between the holotype and the Venice specimen. Most of them can be ascribed to intraspecific variability (individual or ontogenetic), but some are probably caused by mistakes in the preparation or assemblage of the skeletal elements in both specimens. The body length of the Venice skeleton is about 90% the linear size of the holotype. Osteohistological analysis (the first for this taxon) of some long bones, a rib and a dorsal neural spine reveals that the Venice specimen is a sub-adult; this conclusion is supported by somatic evidence of immaturity. The dorsal ‘sail’ formed by the elongated neural spines of the dorsal, sacral and proximal caudal vertebrae characterizes this taxon among ornithopods; a display role is considered to be the most probable function for this bizarre structure. Compared to the mid-1970s, new information from the Venice specimen and many iguanodontian taxa known today allowed for an improved diagnosis of O. nigeriensis.
Collapse
Affiliation(s)
- Filippo Bertozzo
- Earth System Science-AMGC, Vrije Universiteit Brussel, Pleinlaan 2, Brussels/Bruxelles, Belgium
| | - Fabio Marco Dalla Vecchia
- Institut Català de Paleontologia Miquel Crusafont, Sabadell, Spain.,Current affiliation: Soprintendenza Archeologia, Belle Arti e Paesaggio del Friuli Venezia Giulia, Nucleo Operativo di Udine, Udine, Italy
| | - Matteo Fabbri
- Department of Geology and Geophysics, Yale University, New Haven, CT, United States of America
| |
Collapse
|
16
|
McDonald AT, Gates TA, Zanno LE, Makovicky PJ. Anatomy, taphonomy, and phylogenetic implications of a new specimen of Eolambia caroljonesa (Dinosauria: Ornithopoda) from the Cedar Mountain Formation, Utah, USA. PLoS One 2017; 12:e0176896. [PMID: 28489871 PMCID: PMC5425030 DOI: 10.1371/journal.pone.0176896] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 03/26/2017] [Indexed: 11/29/2022] Open
Abstract
Background Eolambia caroljonesa is the most abundant dinosaur in the lower Cenomanian Mussentuchit Member of the Cedar Mountain Formation of Utah, and one of the most completely known non-hadrosaurid iguanodontians from North America. In addition to the large holotype and paratype partial skulls, copious remains of skeletally immature individuals, including three bonebeds, have been referred to E. caroljonesa. Nevertheless, aspects of the postcranial anatomy of this taxon, particularly the pelvic girdle, have remained ambiguous due to the lack of associated postcranial material of larger, more mature individuals. Methodology/Principal findings Here we describe a recently discovered associated partial postcranial skeleton of a large Eolambia caroljonesa. This specimen, FMNH PR 3847, provides new anatomical data regarding the vertebral column and pelvic girdle, supplementing previous diagnoses and descriptions of E. caroljonesa. A new phylogenetic analysis incorporating information from FMNH PR 3847 places E. caroljonesa as a basal hadrosauromorph closely related to Protohadros byrdi from the Cenomanian Woodbine Formation of Texas. Histological analysis of FMNH PR 3847 reveals that it represents a subadult individual eight to nine years of age. Taphonomic analysis indicates that FMNH PR 3847 was preserved in a crevasse splay deposit, along with an unusual abundance of small crocodylomorph material. Conclusions/Significance FMNH PR 3847 provides a wealth of new morphological data, adding to the anatomical and systematic characterization of Eolambia caroljonesa, and histological data, revealing new information on growth history in a basal hadrosauromorph. Taphonomic characterization of FMNH PR 3847 and associated vertebrate material will allow comparison with other vertebrate localities in the Mussentuchit Member of the Cedar Mountain Formation.
Collapse
Affiliation(s)
- Andrew T. McDonald
- Saint Louis Science Center, Saint Louis, Missouri, United States of America
- * E-mail:
| | - Terry A. Gates
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina, United States of America
- North Carolina Museum of Natural Sciences, Raleigh, North Carolina, United States of America
| | - Lindsay E. Zanno
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina, United States of America
- North Carolina Museum of Natural Sciences, Raleigh, North Carolina, United States of America
| | - Peter J. Makovicky
- Section of Earth Sciences, Field Museum of Natural History, Chicago, Illinois, United States of America
| |
Collapse
|
17
|
Sullivan C, Xu X. Morphological Diversity and Evolution of the Jugal in Dinosaurs. Anat Rec (Hoboken) 2016; 300:30-48. [DOI: 10.1002/ar.23488] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 09/30/2016] [Accepted: 09/30/2016] [Indexed: 11/07/2022]
Affiliation(s)
- Corwin Sullivan
- Key Laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences; Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences; 142 Xizhimenwai Dajie Beijing 100044 China
| | - Xing Xu
- Key Laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences; Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences; 142 Xizhimenwai Dajie Beijing 100044 China
| |
Collapse
|
18
|
Brasier MD, Norman DB, Liu AG, Cotton LJ, Hiscocks JEH, Garwood RJ, Antcliffe JB, Wacey D. Remarkable preservation of brain tissues in an Early Cretaceous iguanodontian dinosaur. ACTA ACUST UNITED AC 2016. [DOI: 10.1144/sp448.3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AbstractIt has become accepted in recent years that the fossil record can preserve labile tissues. We report here the highly detailed mineralization of soft tissues associated with a naturally occurring brain endocast of an iguanodontian dinosaur found in c. 133 Ma fluvial sediments of the Wealden at Bexhill, Sussex, UK. Moulding of the braincase wall and the mineral replacement of the adjacent brain tissues by phosphates and carbonates allowed the direct examination of petrified brain tissues. Scanning electron microscopy (SEM) imaging and computed tomography (CT) scanning revealed preservation of the tough membranes (meninges) that enveloped and supported the brain proper. Collagen strands of the meningeal layers were preserved in collophane. The blood vessels, also preserved in collophane, were either lined by, or infilled with, microcrystalline siderite. The meninges were preserved in the hindbrain region and exhibit structural similarities with those of living archosaurs. Greater definition of the forebrain (cerebrum) than the hindbrain (cerebellar and medullary regions) is consistent with the anatomical and implied behavioural complexity previously described in iguanodontian-grade ornithopods. However, we caution that the observed proximity of probable cortical layers to the braincase walls probably resulted from the settling of brain tissues against the roof of the braincase after inversion of the skull during decay and burial.Supplementary material: Information regarding associated fossil material, and additional images, can be found at https://doi.org/10.6084/m9.figshare.c.3519984
Collapse
Affiliation(s)
- Martin D. Brasier
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK
| | - David B. Norman
- Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK
| | - Alexander G. Liu
- Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK
- School of Earth Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Laura J. Cotton
- School of Biological Sciences, The University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong SAR, China
| | | | - Russell J. Garwood
- School of Earth and Environmental Sciences, University of Manchester, Manchester M13 9PL, UK
- Department of Earth Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, UK
| | - Jonathan B. Antcliffe
- Institute of Earth Sciences, University of Lausanne, 1015 Lausanne, Switzerland
- Department of Zoology, University of Oxford, The Tinbergen Building, South Parks Road, Oxford OX1 3PS, UK
- Oxford University Museum of Natural History, Parks Road, Oxford OX1 3PW, UK
| | - David Wacey
- School of Earth Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
- Centre for Microscopy Characterisation and Analysis, and Australian Research Council Centre of Excellence for Core to Crust Fluid Systems, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia
| |
Collapse
|
19
|
Strickson E, Prieto-Márquez A, Benton MJ, Stubbs TL. Dynamics of dental evolution in ornithopod dinosaurs. Sci Rep 2016; 6:28904. [PMID: 27412496 PMCID: PMC4944125 DOI: 10.1038/srep28904] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 06/10/2016] [Indexed: 11/29/2022] Open
Abstract
Ornithopods were key herbivorous dinosaurs in Mesozoic terrestrial ecosystems, with a variety of tooth morphologies. Several clades, especially the ‘duck-billed’ hadrosaurids, became hugely diverse and abundant almost worldwide. Yet their evolutionary dynamics have been disputed, particularly whether they diversified in response to events in plant evolution. Here we focus on their remarkable dietary adaptations, using tooth and jaw characters to examine changes in dental disparity and evolutionary rate. Ornithopods explored different areas of dental morphospace throughout their evolution, showing a long-term expansion. There were four major evolutionary rate increases, the first among basal iguanodontians in the Middle-Late Jurassic, and the three others among the Hadrosauridae, above and below the split of their two major clades, in the middle of the Late Cretaceous. These evolutionary bursts do not correspond to times of plant diversification, including the radiation of the flowering plants, and suggest that dental innovation rather than coevolution with major plant clades was a major driver in ornithopod evolution.
Collapse
Affiliation(s)
- Edward Strickson
- School of Earth Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Albert Prieto-Márquez
- School of Earth Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Michael J Benton
- School of Earth Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Thomas L Stubbs
- School of Earth Sciences, University of Bristol, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| |
Collapse
|
20
|
Shibata M, Jintasakul P, Azuma Y, You HL. A New Basal Hadrosauroid Dinosaur from the Lower Cretaceous Khok Kruat Formation in Nakhon Ratchasima Province, Northeastern Thailand. PLoS One 2015; 10:e0145904. [PMID: 26716981 PMCID: PMC4696827 DOI: 10.1371/journal.pone.0145904] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 12/10/2015] [Indexed: 11/18/2022] Open
Abstract
A new basal hadrosauroid dinosaur from the Lower Cretaceous Khok Kruat Formation of Thailand, Sirindhorna khoratensis gen. et sp. nov is described. The new taxon is based on composite skull and mandible including premaxilla, maxilla, jugal, quadrate, braincases, predentary, dentaries, surangular, and maxillary and dentary teeth. It is diagnostic by such characters as, sagittal crest extending along entire dorsal surface of the parietal and reaching the frontoparietal suture (autapomorphy), transversely straight frontoparietal suture, caudodorsally faced supraoccipital, no participation of the supraoccipital in the foramen magnum, mesiodistally wide leaf-shaped dentary tooth with primary and secondary ridges on the lingual surface of the crown, perpendicularly-erected and large coronoid process of dentary, and nonvisible antorbital fossa of the maxilla in lateral view. Phylogenetic analysis revealed S. khoratensis as among the most basal hadrosauroids. Sirindhorna khoratensis is the best-preserved iguanodontian ornithopod in Southeast Asia and sheds new light to resolve the evolution of basal hadrosauriforms.
Collapse
Affiliation(s)
- Masateru Shibata
- Institute of Dinosaur Research, Fukui Prefectural University, 4–1–1 Kenjojima, Matsuoka, Eiheiji–Cho, Fukui, 910–1195, Japan
- Fukui Prefectural Dinosaur Museum, 51–11 Muroko, Terao, Katsuyama, Fukui, 911–8601, Japan
- * E-mail:
| | - Pratueng Jintasakul
- Northeastern Research Institute of Petrified Wood and Mineral Resources, Nakhon Ratchasima Rajabhat University, 184 Moo 7 Suranaree Subdistict, Mueang, Nakhon Ratchasima District, Nakhon Ratchasima, 30000, Thailand
| | - Yoichi Azuma
- Institute of Dinosaur Research, Fukui Prefectural University, 4–1–1 Kenjojima, Matsuoka, Eiheiji–Cho, Fukui, 910–1195, Japan
- Fukui Prefectural Dinosaur Museum, 51–11 Muroko, Terao, Katsuyama, Fukui, 911–8601, Japan
| | - Hai-Lu You
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, 100044, PR China
| |
Collapse
|
21
|
Boyd CA. The systematic relationships and biogeographic history of ornithischian dinosaurs. PeerJ 2015; 3:e1523. [PMID: 26713260 PMCID: PMC4690359 DOI: 10.7717/peerj.1523] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 11/30/2015] [Indexed: 11/23/2022] Open
Abstract
The systematic relationships of taxa traditionally referred to as 'basal ornithopods' or 'hypsilophodontids' remain poorly resolved since it was discovered that these taxa are not a monophyletic group, but rather a paraphyletic set of neornithischian taxa. Thus, even as the known diversity of these taxa has dramatically increased over the past two decades, our knowledge of their placement relative to each other and the major ornithischian subclades remained incomplete. This study employs the largest phylogenetic dataset yet compiled to assess basal ornithischian relationships (255 characters for 65 species level terminal taxa). The resulting strict consensus tree is the most well-resolved, stratigraphically consistent hypothesis of basal ornithischian relationships yet hypothesized. The only non-iguanodontian ornithopod (=basal ornithopod) recovered in this analysis is Hypsilophodon foxii. The majority of former 'hypsilophodontid' taxa are recovered within a single clade (Parksosauridae) that is situated as the sister-taxon to Cerapoda. The Parksosauridae is divided between two subclades, the Orodrominae and the Thescelosaurinae. This study does not recover a clade consisting of the Asian taxa Changchunsaurus, Haya, and Jeholosaurus (=Jeholosauridae). Rather, the former two taxa are recovered as basal members of Thescelosaurinae, while the latter taxon is recovered in a clade with Yueosaurus near the base of Neornithischia.The endemic South American clade Elasmaria is recovered within the Thescelosaurinae as the sister taxon to Thescelosaurus. This study supports the origination of Dinosauria and the early diversification of Ornithischia within Gondwana. Neornithischia first arose in Africa by the Early Jurassic before dispersing to Asia before the late Middle Jurassic, where much of the diversification among non-cerapodan neornithischians occurred. Under the simplest scenario the Parksosauridae originated in North America, with at least two later dispersals to Asia and one to South America. However, when ghost lineages are considered, an alternate dispersal hypothesis has thescelosaurines dispersing from Asia into South America (via North America) during the Early Cretaceous, then back into North America in the latest Cretaceous. The latter hypothesis may explain the dominance of orodromine taxa prior to the Maastrichtian in North America and the sudden appearance and wide distribution of thescelosaurines in North America beginning in the early Maastrichtian. While the diversity of parksosaurids has greatly increased over the last fifteen years, a ghost lineage of over 40 myr is present between the base of Parksosauridae and Cerapoda, indicating that much of the early history and diversity of this clade is yet to be discovered. This new phylogenetic hypothesis provides a comprehensive framework for testing further hypotheses regarding evolutionary patterns and processes within Ornithischia.
Collapse
Affiliation(s)
- Clint A. Boyd
- North Dakota Geological Survey, Bismarck, ND, United States
| |
Collapse
|
22
|
Gasulla JM, Escaso F, Narváez I, Ortega F, Sanz JL. A New Sail-Backed Styracosternan (Dinosauria: Ornithopoda) from the Early Cretaceous of Morella, Spain. PLoS One 2015; 10:e0144167. [PMID: 26673161 PMCID: PMC4691198 DOI: 10.1371/journal.pone.0144167] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 11/13/2015] [Indexed: 11/18/2022] Open
Abstract
A new styracosternan ornithopod genus and species is here described based on a partial postcranial skeleton and an associated dentary tooth of a single specimen from the Arcillas de Morella Formation (Early Cretaceous, late Barremian) at the Morella locality, (Castellón, Spain). Morelladon beltrani gen. et sp. nov. is diagnosed by eight autapomorphic features. The set of autapomorphies includes: very elongated and vertical neural spines of the dorsal vertebrae, midline keel on ventral surface of the second to fourth sacral vertebrae restricted to the anterior half of the centrum, a posterodorsally inclined medial ridge on the postacetabular process of the ilium that meets its dorsal margin and distal end of the straight ischial shaft laterally expanded, among others. Phylogenetic analyses reveal that the new Iberian form is more closely related to its synchronic and sympatric contemporary European taxa Iguanodon bernissartensis and Mantellisaurus atherfieldensis, known from Western Europe, than to other Early Cretaceous Iberian styracosternans (Delapparentia turolensis and Proa valdearinnoensis). The recognition of Morelladon beltrani gen. et sp. nov. indicates that the Iberian Peninsula was home to a highly diverse medium to large bodied styracosternan assemblage during the Early Cretaceous.
Collapse
Affiliation(s)
- José Miguel Gasulla
- Unidad de Paleontología, Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain
| | - Fernando Escaso
- Grupo de Biología Evolutiva, Universidad Nacional de Educación a Distancia, Madrid, Spain
- * E-mail:
| | - Iván Narváez
- Grupo de Biología Evolutiva, Universidad Nacional de Educación a Distancia, Madrid, Spain
| | - Francisco Ortega
- Grupo de Biología Evolutiva, Universidad Nacional de Educación a Distancia, Madrid, Spain
| | - José Luis Sanz
- Unidad de Paleontología, Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain
| |
Collapse
|
23
|
Boyd CA, Pagnac DC. Insight on the anatomy, systematic relationships, and age of the Early Cretaceous ankylopollexian dinosaur Dakotadon lakotaensis. PeerJ 2015; 3:e1263. [PMID: 26417544 PMCID: PMC4582955 DOI: 10.7717/peerj.1263] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 09/03/2015] [Indexed: 11/20/2022] Open
Abstract
Knowledge regarding the early evolution within the dinosaurian clade Ankylopollexia drastically increased over the past two decades, in part because of an increase in described taxa from the Early Cretaceous of North America. These advances motivated the recent completion of extensive preparation and conservation work on the holotype and only known specimen of Dakotadon lakotaensis, a basal ankylopollexian from the Lakota Formation of South Dakota. That specimen (SDSM 8656) preserves a partial skull, lower jaws, a single dorsal vertebra, and two caudal vertebrae. That new preparation work exposed several bones not included in the original description and revealed that other bones were previously misidentified. The presence of extensive deformation in areas of the skull is also noted that influenced inaccuracies in prior descriptions and reconstructions of this taxon. In addition to providing an extensive re-description of D. lakotaensis, this study reviews previously proposed diagnoses for this taxon, identifies two autapomorphies, and provides an extensive differential diagnosis. Dakotadon lakotaensis is distinct from the only other ankylopollexian taxon known from the Lakota Formation, Osmakasaurus depressus, in the presence of two prominent, anteroposteriorly oriented ridges on the ventral surfaces of the caudal vertebrae, the only overlapping material preserved between these taxa. The systematic relationships of D. lakotaensis are evaluated using both the parsimony and posterior probability optimality criteria, with both sets of analyses recovering D. lakotaensis as a non-hadrosauriform ankylopollexian that is more closely related to taxa from the Early Cretaceous (e.g., Iguanacolossus, Hippodraco, and Theiophytalia) than to more basally situated taxa from the Jurassic (e.g., Camptosaurus, Uteodon). This taxonomic work is supplemented by field work that relocated the type locality, confirming its provenance from unit L2 (lower Fuson Member equivalent) of the Lakota Formation. Those data, combined with recently revised ages for the members of the Lakota Formation based on charophyte and ostracod biostratigraphy, constrain the age of this taxon to the late Valanginian to early Barremian.
Collapse
Affiliation(s)
- Clint A. Boyd
- North Dakota Geological Survey, Bismarck, North Dakota, USA
| | - Darrin C. Pagnac
- Department of Geology and Geological Engineering, South Dakota School of Mines and Technology, Rapid City, South Dakota, USA
| |
Collapse
|