DOCSLIB.ORG

A New Specimen of Eurylambda Aequicrurius and Considerations on ``Symmetrodont'' Dentition and Relationships

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
A New Specimen of Eurylambda Aequicrurius and Considerations on ``Symmetrodont'' Dentition and Relationships PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY CENTRAL PARK WEST AT 79TH STREET, NEW YORK, NY 10024 Number 3398, 15 pp., 4 ®gures March 27, 2003 A New Specimen of Eurylambda aequicrurius and Considerations on ``Symmetrodont'' Dentition and Relationships GUILLERMO W. ROUGIER,1 BARTON K. SPURLIN,2 AND PETER K. KIK3 ABSTRACT A new specimen of the tinodontid ``symmetrodont'' Eurylambda (Simpson, 1925a, 1929) from the Late Jurassic Como Bluff Quarry, Morrison Formation, is described. The specimen, a complete upper left molariform, is probably an M1. The major crown cusps of Eurylambda show similarities to those of triconodontids on the one hand and to spalacotherioids on the other. Cusp B of basal mammaliaforms is tentatively proposed as homologous with the cusp traditionally described as a stylocone in Eurylambda and with cusp B9 of Peralestes. These homologies imply that the stylocone is ancestrally a small cusp in the lineage leading to Theria and that the development of a parastylar lobe or ``hook'' is a derived feature of post-tinodontid mammals. If accepted, this scenario results in a more complex origin for the therian upper molar than previously recognized. Wear facet 1 (Crompton, 1971) of holotherians would not be homologous between Kuehneotherium±Eu- rylambda±Zhangheotherium, on the one hand, and the therians, on the other. INTRODUCTION in a bias favoring the preservation of lower teeth and jaws. Therefore, our knowledge of Information on the upper molars of early dental evolution during the Mesozoic relies Mesozoic mammals is sparse, due largely to heavily on mandibular and lower molar mor- the mechanical fragility of the maxilla when phology (Crompton, 1971; Prothero, 1981). compared with the mandible, which results Discovery of upper molariforms is always a 1 Research Associate, Division of Paleontology, American Museum of Natural History. Assistant Professor, Department of Anatomical Sciences and Neurobiology, School of Medicine, University of Louisville, Louisville, KY 40292. e-mail: [email protected] 2 Department of Neurology, School of Medicine, University of Louisville, Louisville, KY 40292. e-mail: [email protected] 3 Department of Anatomical Sciences and Neurobiology, School of Medicine, University of Louisville, Louis- ville, KY 40292. e-mail: [email protected] Copyright q American Museum of Natural History 2003 ISSN 0003-0082 2 AMERICAN MUSEUM NOVITATES NO. 3398 welcome addition because it allows the eval- sessing the bases of both roots. The crown uation of models of evolutionary transfor- was broken into halves at the base of the mation that have been based primarily on paracone and has been previously repaired. lower teeth, with occluding upper teeth being The crown of the new specimen is more buc- based on hypothetical reconstructions (Mills, colingually compressed than the type speci- 1964; Kermack et al., 1964; Crompton, men and is slightly longer mesiodistally, with 1971). the major cusps forming an obtuse angle of We report here on an isolated upper left about 1718 (with the type specimen forming molariform of Eurylambda aequicrurius an angle of about 1688). These features sug- (Simpson, 1925a, 1929). This is only the sec- gest that the new specimen is a more anterior ond specimen known for this taxon originally tooth than is the type. If tooth variance in described as Amphidon aequicrurius (Simp- other symmetrodonts is used as a model (Ci- son, 1925a) from the Late Jurassic Morrison felli, 1999; Cifelli and Gordon, 1999; Cifelli Formation in Wyoming. The new specimen and Madsen, 1999; Hu et al., 1997, 1998; was collected at Como Bluff Quarry in 1883 undescribed specimen in prep.), the new by members of the O.C. Marsh expedition tooth probably represents the position direct- and catalogued at the National Museum of ly mesial to the type, which was originally Natural History as an undetermined Meso- regarded as M1 (Simpson, 1925a, 1929) but zoic mammal tooth with the number USNM is here interpreted as a probable M2. How- 2846. Como Bluff is also the locality where ever, USNM 2846 has a slightly more pro- the Yale University party collected the type nounced ecto¯exus than does the type. This specimen of Eurylambda. becomes more pronounced in distal elements Discovery of a second specimen of Eury- of other ``symmetrodonts'', that is zhang- lambda is important because the type, a frag- heotheriids (Hu et al., 1997, 1998; unde- mentary maxilla with one tooth, has previ- scribed specimen in prep.), spalacotheriids ously been the only model for the upper den- (Cifelli and Gordon, 1999; Cifelli and Mad- tition of basal or obtuse angled ``symmetro- sen, 1999) and Peralestes (Owen, 1871; donts'' (Crompton and Jenkins, 1967, 1968; Simpson, 1928; Clemens, 1963). This latter Crompton, 1971; Ensom and Sigogneau- consideration introduces some doubts about Russell, 2000). Furthermore, the incomplete the more mesial position of USNM 2846 type is missing the parastylar region of the proposed here. tooth. Eurylambda has been suggested to be The crown has the shape of an elongated a junior synonym of Tinodon (Prothero, ``D'', with the straight side oriented buccally 1981; Fox, 1985; McKenna and Bell, 1997; and slightly excavated by the shallow ecto- Sigogneau-Russell and Ensom, 1998; Ensom ¯exus. Six cusps are fairly regularly placed and Sigogneau-Russell, 2000) and we tenta- on the outline of the ``D''. The largest of tively follow this interpretation here (see be- them is the centrally placed paracone (cusp low), although for convenience we continue A in terminology of Crompton and Jenkins, to use the name Eurylambda for the upper 1968). Three cusps are distal to the paracone: molars. the metacone (cusp C), cusp D, and a small metastyle (following the terminology of SYSTEMATIC PALEONTOLOGY Crompton and Jenkins (1967) and subse- quent modi®cations) forming the extreme TINODONTIDAE FOX, 1985 distolabial corner of the crown. Mesial to the paracone is the fairly lingual cusp B9 (as in- Tinodon bellus Marsh, 1879 (Amphidon aequi- terpreted by Hu et al. (1997, 1998) or ``cusp crurius Simpson, 1925a; Eurylambda Simpson, 1929). on anterior crest'' of Patterson (1956), and a small stylocone in the mesiobuccal corner of the crown (see discussion below). The styl- DESCRIPTION ocone is joined to cusp B9 by a sharp crest (Figures 1, 2) that descends abruptly from the mesial slope MATERIAL: The specimen (USNM 2846) is of B9. The small stylocone extends distally an isolated complete left upper molar pos- as a fairly robust crest that reaches the mid- 2003 ROUGIER ET AL.: EURYLAMBDA AEQUICRURIUS 3 dle of the buccal surface of B9. The area buc- gard to the main axis of the tooth, and sub- comesial to cusp B9 is raised and forms a equal in size. They differ markedly from the small platform which sets off a small thick- condition in Spalacotheroides (Cifelli and ening of the mesial slope of the stylocone. Madsen, 1999), whose roots are mesiodistal- Cusp B9 is a main cusp of the crown and ly compressed and parallel to each other. is not connected to a cingulum of any kind. It has a concave mesial face and a teardrop- DISCUSSION shaped wear facet that truncates its apex. Dis- tal to its apex, cusp B9 is connected to the The importance of Eurylambda in our un- massive face of the paracone by a short, near- derstanding of early ``symmetrodont'' rela- ly horizontal ridge. A shallow notch is formed tionships has recently been stressed by En- at the intersection of the distal crest of cusp som and Sigogneau-Russell (2000). Eury- B9 and the mesial edge of the paracone. lambda, putatively a junior synonym of Tin- The paracone is the largest and tallest odon, represents one of the few examples of cusp, being twice as high as the next highest upper tooth morphology among ``symmetro- cusp in the crown, the metacone. The para- donts'' and it has played a crucial role in the cone is slightly asymmetrical mesiodistally, study of dental occlusion (Crompton and with a blunter, more vertical mesial edge and Jenkins, 1967, 1968; Crompton, 1971). Eur- a sharper, longer, and more gently sloping ylambda represents the archetype for basal distal crest. The lingual side of the paracone nontribosphenic holotheres (Hopson, 1994; is almost ¯at while the buccal side is strongly Wible et al., 1995). convex. These differences give the paracone Ensom and Sigogneau-Russell (2000) re- a conspicuous hooklike shape. cently described a new species of Tinodon, The metacone (cusp C) is separated by Tinodon micron, from the Purbeck Lime- deep notches from both the paracone and stone Group, Lower Cretaceous of England. cusp D. It is a fairly symmetrical cusp, al- The type specimen is a lower molar that though the distal ridge is somewhat longer agrees quite closely with the American spe- and less vertical. Its lingual face is grooved cies of Tinodon. In addition to lower molars, by a distinctive wear facet, which covers not Ensom and Sigogneau-Russell (2000) attri- only cusp D, but extends to the metastyle. buted an isolated upper molar to the same Cusp D (which may be interpreted as the species and compared it to Eurylambda.We larger of two metastylar cusps) is separated concur with their analysis in noting the close by a relatively shallow embrasure from the similarities between the two North American metacone (C) and by a deep notch from the specimens of Eurylambda and the English metastyle. The wear facet mentioned above specimen, DORCM GS 694, referred to T. ¯attens its lingual surface while its labial as- micron. The main difference between the pect is strongly convex. The distal metastyle American specimens of Eurylambda and that is a poorly differentiated small cuspule that from the Purbeck is the presence of a well- forms a small, sharp posterior edge for inter- developed cusp B9 in the former, which is locking with the following molar.
Load more

Recommended publications
  • Reptile-Like Physiology in Early Jurassic Stem-Mammals
    bioRxiv preprint doi: https://doi.org/10.1101/785360; this version posted October 10, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Title: Reptile-like physiology in Early Jurassic stem-mammals Authors: Elis Newham1*, Pamela G. Gill2,3*, Philippa Brewer3, Michael J. Benton2, Vincent Fernandez4,5, Neil J. Gostling6, David Haberthür7, Jukka Jernvall8, Tuomas Kankanpää9, Aki 5 Kallonen10, Charles Navarro2, Alexandra Pacureanu5, Berit Zeller-Plumhoff11, Kelly Richards12, Kate Robson-Brown13, Philipp Schneider14, Heikki Suhonen10, Paul Tafforeau5, Katherine Williams14, & Ian J. Corfe8*. Affiliations: 10 1School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol, UK. 2School of Earth Sciences, University of Bristol, Bristol, UK. 3Earth Science Department, The Natural History Museum, London, UK. 4Core Research Laboratories, The Natural History Museum, London, UK. 5European Synchrotron Radiation Facility, Grenoble, France. 15 6School of Biological Sciences, University of Southampton, Southampton, UK. 7Institute of Anatomy, University of Bern, Bern, Switzerland. 8Institute of Biotechnology, University of Helsinki, Helsinki, Finland. 9Department of Agricultural Sciences, University of Helsinki, Helsinki, Finland. 10Department of Physics, University of Helsinki, Helsinki, Finland. 20 11Helmholtz-Zentrum Geesthacht, Zentrum für Material-und Küstenforschung GmbH Germany. 12Oxford University Museum of Natural History, Oxford, OX1 3PW, UK. 1 bioRxiv preprint doi: https://doi.org/10.1101/785360; this version posted October 10, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 13Department of Anthropology and Archaeology, University of Bristol, Bristol, UK. 14Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK.
    [Show full text]
  • A New Gobiconodontid Mammal from the Early Cretaceous of Spain and Its Palaeogeographic Implications
    A new gobiconodontid mammal from the Early Cretaceous of Spain and its palaeogeographic implications Gloria Cuenca-Bescós and José I. Canudo Acta Palaeontologica Polonica 48 (4), 2003: 575-582 A new gobiconodontid from Vallipón (Teruel, Spain) represents the first record of this family in Europe. The site has a diverse fossil assemblage mainly composed of isolated bones and teeth probably accumulated by tidal action and water streams in an ancient beach of upper Barremian, in the transitional marine-continental sediments of the Artoles Formation. The new gobiconodontid consist of an isolated upper molar, smaller in size than that element in other gobiconodontids, with a robust cusp A, characterised by lateral bulges on each mesial and distal flanges of that cusp, and a discontinuous cingulum raised at the lingual side. The oclusal outline is smooth compared with Gobiconodon borissiaki, Gobiconodon hoburensis, or Gobiconodon ostromi. The Gobiconodontidae record is exclusively Laurasiatic. The oldest gobiconodontid fossil remains are Hauterivian; though their probable origin has to be found at the Late Jurassic in Central Asia (as inferred from derived character of the first gobiconodontids as well as phylogenetic relationships). At the end of the Early Cretaceous they expanded throughout Laurasia as indicated by findings in Asia, North America and Spain. Two dispersion events spread gobiconodontids: to the West (Europe) in the Barremian and to the East (North America) during the Aptian/Albian. Key words: Cretaceous, Barremian, Mammalia, Gobiconodontidae, Europe, palaeogeography. Gloria Cuenca−Bescós [[email protected]], José Ignacio Canudo [[email protected]], Area y Museo de Paleontología, Departamento de Ciencias de la Tierra, Universidad de Zaragoza, 50009 Zaragoza, Spain.
    [Show full text]
  • A Dated Phylogeny of Marsupials Using a Molecular Supermatrix and Multiple Fossil Constraints
    Journal of Mammalogy, 89(1):175–189, 2008 A DATED PHYLOGENY OF MARSUPIALS USING A MOLECULAR SUPERMATRIX AND MULTIPLE FOSSIL CONSTRAINTS ROBIN M. D. BECK* School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia Downloaded from https://academic.oup.com/jmammal/article/89/1/175/1020874 by guest on 25 September 2021 Phylogenetic relationships within marsupials were investigated based on a 20.1-kilobase molecular supermatrix comprising 7 nuclear and 15 mitochondrial genes analyzed using both maximum likelihood and Bayesian approaches and 3 different partitioning strategies. The study revealed that base composition bias in the 3rd codon positions of mitochondrial genes misled even the partitioned maximum-likelihood analyses, whereas Bayesian analyses were less affected. After correcting for base composition bias, monophyly of the currently recognized marsupial orders, of Australidelphia, and of a clade comprising Dasyuromorphia, Notoryctes,and Peramelemorphia, were supported strongly by both Bayesian posterior probabilities and maximum-likelihood bootstrap values. Monophyly of the Australasian marsupials, of Notoryctes þ Dasyuromorphia, and of Caenolestes þ Australidelphia were less well supported. Within Diprotodontia, Burramyidae þ Phalangeridae received relatively strong support. Divergence dates calculated using a Bayesian relaxed molecular clock and multiple age constraints suggested at least 3 independent dispersals of marsupials from North to South America during the Late Cretaceous or early Paleocene. Within the Australasian clade, the macropodine radiation, the divergence of phascogaline and dasyurine dasyurids, and the divergence of perameline and peroryctine peramelemorphians all coincided with periods of significant environmental change during the Miocene. An analysis of ‘‘unrepresented basal branch lengths’’ suggests that the fossil record is particularly poor for didelphids and most groups within the Australasian radiation.
    [Show full text]
  • Miocene Mammal Reveals a Mesozoic Ghost Lineage on Insular New Zealand, Southwest Pacific
    Miocene mammal reveals a Mesozoic ghost lineage on insular New Zealand, southwest Pacific Trevor H. Worthy*†, Alan J. D. Tennyson‡, Michael Archer§, Anne M. Musser¶, Suzanne J. Hand§, Craig Jonesʈ, Barry J. Douglas**, James A. McNamara††, and Robin M. D. Beck§ *School of Earth and Environmental Sciences, Darling Building DP 418, Adelaide University, North Terrace, Adelaide 5005, South Australia, Australia; ‡Museum of New Zealand Te Papa Tongarewa, P.O. Box 467, Wellington 6015, New Zealand; §School of Biological, Earth and Environmental Sciences, University of New South Wales, New South Wales 2052, Australia; ¶Australian Museum, 6-8 College Street, Sydney, New South Wales 2010, Australia; ʈInstitute of Geological and Nuclear Sciences, P.O. Box 30368, Lower Hutt 5040, New Zealand; **Douglas Geological Consultants, 14 Jubilee Street, Dunedin 9011, New Zealand; and ††South Australian Museum, Adelaide, South Australia 5000, Australia Edited by James P. Kennett, University of California, Santa Barbara, CA, and approved October 11, 2006 (sent for review July 8, 2006) New Zealand (NZ) has long been upheld as the archetypical Ma) dinosaur material (13) and isolated moa bones from marine example of a land where the biota evolved without nonvolant sediments up to 2.5 Ma (1, 14), the terrestrial record older than terrestrial mammals. Their absence before human arrival is mys- 1 Ma is extremely limited. Until now, there has been no direct terious, because NZ was still attached to East Antarctica in the Early evidence for the pre-Pleistocene presence in NZ of any of its Cretaceous when a variety of terrestrial mammals occupied the endemic vertebrate lineages, particularly any group of terrestrial adjacent Australian portion of Gondwana.
    [Show full text]
  • Constraints on the Timescale of Animal Evolutionary History
    Palaeontologia Electronica palaeo-electronica.org Constraints on the timescale of animal evolutionary history Michael J. Benton, Philip C.J. Donoghue, Robert J. Asher, Matt Friedman, Thomas J. Near, and Jakob Vinther ABSTRACT Dating the tree of life is a core endeavor in evolutionary biology. Rates of evolution are fundamental to nearly every evolutionary model and process. Rates need dates. There is much debate on the most appropriate and reasonable ways in which to date the tree of life, and recent work has highlighted some confusions and complexities that can be avoided. Whether phylogenetic trees are dated after they have been estab- lished, or as part of the process of tree finding, practitioners need to know which cali- brations to use. We emphasize the importance of identifying crown (not stem) fossils, levels of confidence in their attribution to the crown, current chronostratigraphic preci- sion, the primacy of the host geological formation and asymmetric confidence intervals. Here we present calibrations for 88 key nodes across the phylogeny of animals, rang- ing from the root of Metazoa to the last common ancestor of Homo sapiens. Close attention to detail is constantly required: for example, the classic bird-mammal date (base of crown Amniota) has often been given as 310-315 Ma; the 2014 international time scale indicates a minimum age of 318 Ma. Michael J. Benton. School of Earth Sciences, University of Bristol, Bristol, BS8 1RJ, U.K. [email protected] Philip C.J. Donoghue. School of Earth Sciences, University of Bristol, Bristol, BS8 1RJ, U.K. [email protected] Robert J.
    [Show full text]
  • Mammalian Origins Major Groups of Synapsida
    Mammalogy 4764 9/16/2009 Chapter 4 “Reptile” Mammalian Origins Early mammal Carnivore Amniota Herbivore Feldhamer Table 4.1 Savage and Long 1986 Major Fig. 3.2, Vaughn, Fig. 4.1, Feldhamer groups Mammalian Origins of Dimetrodon Overview Synapsida Synapsids Pelycosaurs and Therapsids First Mammals Mesozoic Era appear Feldhamer Fig. 4.2 Cenozoic Era radiate Savage and Long 1986 Pelycosaur Skull, jaw musculature, and teeth Cynodontia -- Advanced, predaceous therapsids Pelycosaur Scymnognathus Cynognathus Therapsid Early Cynodont Derived Therapsid/Mammal Primitive Late Cynodont Fig. 3.2, Vaughn Thrinaxodon Fig 4.3 & 4, Feldhamer 1 Mammalogy 4764 9/16/2009 Skeletal transition Extinction of Cynodonts Possibly competition from dinosaurs Pelycosaur Early Cynodonts were dog-size, last surviving were squirrel sized Fig. 4.15 Mammals that survived while Cynodonts went extinct (contemporary) were mouse-sized. Cynodont Thrinaxodon Modern Mammal Fig. 3.5, Vaughn Fig. 4.16c, Early Cynodont Early mammals Changes in land masses Feldhamer 4.11 200 - 250 million years ago Derived characters: Dentary/squamosal jaw articulation Diphyodont dentition 200 MYA 180 MYA Mammary glands Secondary palate Early Mid- Viviparity (loss of eggshell) When? Jurassic Jurassic 65 MYA 135 MYA Early Early Cretaceous Cenozoic Feldhamer 4.5, 4.9 Skull and teeth of mammals 2 Mammalogy 4764 9/16/2009 Teeth and Dentition of Mammals Teeth Heterodont teeth with different functions Differentiated on the basis of function, resulting in increased One of the major keys efficiency acquiring and digesting food. to success of mammals Teeth occur in 3 bones of skull: Teeth of mammals are premaxilla, maxilla, dentary extremely variable with different diets -- more than other taxa Feldhamer et al.
    [Show full text]
  • Mammals from the Mesozoic of Mongolia
    Mammals from the Mesozoic of Mongolia Introduction and Simpson (1926) dcscrihed these as placental (eutherian) insectivores. 'l'he deltathcroids originally Mongolia produces one of the world's most extraordi- included with the insectivores, more recently have narily preserved assemblages of hlesozoic ma~nmals. t)een assigned to the Metatheria (Kielan-Jaworowska Unlike fossils at most Mesozoic sites, Inany of these and Nesov, 1990). For ahout 40 years these were the remains are skulls, and in some cases these are asso- only Mesozoic ~nanimalsknown from Mongolia. ciated with postcranial skeletons. Ry contrast, 'I'he next discoveries in Mongolia were made by the Mesozoic mammals at well-known sites in North Polish-Mongolian Palaeontological Expeditions America and other continents have produced less (1963-1971) initially led by Naydin Dovchin, then by complete material, usually incomplete jaws with den- Rinchen Barsbold on the Mongolian side, and Zofia titions, or isolated teeth. In addition to the rich Kielan-Jaworowska on the Polish side, Kazi~nierz samples of skulls and skeletons representing Late Koualski led the expedition in 1964. Late Cretaceous Cretaceous mam~nals,certain localities in Mongolia ma~nmalswere collected in three Gohi Desert regions: are also known for less well preserved, but important, Bayan Zag (Djadokhta Formation), Nenlegt and remains of Early Cretaceous mammals. The mammals Khulsan in the Nemegt Valley (Baruungoyot from hoth Early and Late Cretaceous intervals have Formation), and llcrmiin 'ISav, south-\vest of the increased our understanding of diversification and Neniegt Valley, in the Red beds of Hermiin 'rsav, morphologic variation in archaic mammals. which have heen regarded as a stratigraphic ecluivalent Potentially this new information has hearing on the of the Baruungoyot Formation (Gradzinslti r't crl., phylogenetic relationships among major branches of 1977).
    [Show full text]
  • Femur of a Morganucodontid Mammal from the Middle Jurassic of Central Russia
    Femur of a morganucodontid mammal from the Middle Jurassic of Central Russia PETR P. GAMBARYAN and ALEXANDER 0.AVERIANOV Gambaryan, P.P. & Averianov, A.O. 2001. Femur of a morganucodontid mammal from the Middle Jurassic of Central Russia. -Acta Palaeontologica Polonica 46,1,99-112. We describe a nearly complete mammalian femur from the Middle Jurassic (upper Bathonian) from Peski quarry, situated some 100 km south east of Moscow, central Rus- sia. It is similar to the femora of Morganucodontidae in having a globular femoral head, separated from the greater trochanter and reflected dorsally, fovea capitis present, both trochanters triangular and located on the same plane, distal end flat, mediolaterally expanded, and somewhat bent ventrally, and in the shape and proportions of distal condyles. It is referred to as Morganucodontidae gen. et sp. indet. It is the first representa- tive of this group of mammals in Eastern Europe from the third Mesozoic mammal local- ity discovered in Russia. Exquisite preservation of the bone surface allowed us to recon- struct partial hind limb musculature. We reconstruct m. iliopsoas as inserting on the ridge, which starts at the lesser trochanter and extends along the medial femoral margin for more than half of the femur length. On this basis we conclude that the mode of loco- motion of the Peski morganucodontid was similar to that of modern echidnas. During the propulsive phase the femur did not retract and the step elongation was provided by pronation of the femur. Key words : Mammalia, Morganucodontidae, femur, anatomy, locomotion, Jurassic, Russia. Petr P. Gambaryan [[email protected]] and Alexander 0.
    [Show full text]
  • Panciroli, Elsa, Benson, Roger B J and Butler, Richard J (2018) New
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by National Museums Scotland Research Repository Panciroli, Elsa, Benson, Roger B J and Butler, Richard J (2018) New partial dentaries of amphitheriid mammal Palaeoxonodon ooliticus from Scotland, and posterior dentary morphology in early cladotherians. Acta Palaeontologica Polonica, 63. ISSN 1732-2421 10.4202/app.00434.2017 http://repository.nms.ac.uk/2048 Deposited on: 31 May 2018 NMS Repository – Research publications by staff of the National Museums Scotland http://repository.nms.ac.uk/ http://app.pan.pl/SOM/app63-Panciroli_etal_SOM.pdf SUPPLEMENTARY ONLINE MATERIAL FOR New partial dentaries of amphitheriid mammalian Palaeoxonodon ooliticus from Scotland, and posterior dentary morphology in early cladotherians Elsa Panciroli, Roger B.J. Benson, and Richard J. Butler Published in Acta Palaeontologica Polonica 2018, 63(X): xxx-xxx. https://doi.org/10.4202/app.00434.2017 Supplementary Online Material SOM 1. 3D model of Palaeoxonodon ooliticus NMS G.1992.47.123 from the Isle of Skye, Scotland, available at http://app.pan.pl/SOM/app63-Panciroli_etal_SOM/SOM_1.stl SOM 2. 3D model of Palaeoxonodon ooliticus NMS G.1992.47.123 from the Isle of Skye, Scotland, dentition only, available at http://app.pan.pl/SOM/app63-Panciroli_etal_SOM/SOM_2.stl SOM 3. 3D model of Palaeoxonodon ooliticus NMS G.2017.37.1 from the Isle of Skye, Scotland, available at http://app.pan.pl/SOM/app63-Panciroli_etal_SOM/SOM_3.stl SOM 4. 3D model of Palaeoxonodon ooliticus NMS G.2017.37.1 from the Isle of Skye, Scotland, dentition only, available at http://app.pan.pl/SOM/app63-Panciroli_etal_SOM/SOM_4.stl SOM 5.
    [Show full text]
  • SI Appendix the Oldest Modern Therian Mammal from Europe And
    SI Appendix The oldest modern therian mammal from Europe and its bearing on stem marsupial paleobiogeography RomainVulloa,b,1, Emmanuel Gheerbrantc, Christian de Muizonc, Didier Néraudeaub Table of contents • Part I. List of characters studied. • Part II. Character matrix. • Part III. TNT analysis, cladograms, and characters at nodes. • Part IV. References. Part I List of characters studied (mostly molars) All characters are additive, except when mentioned. 1. Molar cusp shape: sharp, gracile (0), low but still acute (1), or inflated, robust, low, bulbous (2). Arcantiodelphys (1). 2. Protocone: lacking (undifferentiated from the lingual cingulum) (0), incipient (very small) but inflated with protocristae and functionnal (1), or well developed, with large protofossa (2). Arcantiodelphys (2). Kielantherium : upper molars features are based on the new material reported by Lopatin and Averianov (1). 3. Stylar shelf: wide (0), very wide (1), or narrow (2). Arcantiodelphys (0). Character non additive. 4. Protocone development: mesio-distally narrow and compressed (0) or well-developed (both mesio-distally and labio-lingually) and uncompressed (1). Arcantiodelphys (1). 5. Height of the protocone relative to the paracone and metacone (whichever is highest of the latter two): protocone markedly lower (less than 70%) (0), protocone of intermediate height (70%~80%) (1), or protocone near the height of paracone and metacone (within 80%) (2). Arcantiodelphys (2). 6. Stylar cusp C: absent (0), present but weak (1), or present and well developed (2). Arcantiodelphys (1). 7. Stylar cusp D: absent (0), present but weak (1), or present and well developed (2). Arcantiodelphys (1). 8. Paraconule and metaconule: absent or weak (0) or present and well developed (1).
    [Show full text]
  • Early Cretaceous Amphilestid ('Triconodont') Mammals from Mongolia
    Early Cretaceous amphilestid ('triconodont') mammals from Mongolia ZOFIAKIELAN-JAWOROWSKA and DEMBERLYIN DASHZEVEG Kielan-Jaworowską Z. &Daslueveg, D. 1998. Early Cretaceous amphilestid (.tricono- dont') mammals from Mongotia. - Acta Pal.aeontol.ogicaPolonica,43,3, 413438. Asmall collection of ?Aptianor ?Albian amphilestid('triconodont') mammals consisting of incomplete dentaries and maxillae with teeth, from the Khoboor localiĘ Guchin Us counĘ in Mongolia, is described. Grchinodon Troftmov' 1978 is regarded a junior subjective synonym of GobiconodonTroftmov, 1978. Heavier wear of the molariforms M3 andM4than of themore anteriorone-M2 in Gobiconodonborissiaki gives indirect evidence formolariformreplacement in this taxon. The interlocking mechanismbetween lower molariforms n Gobiconodon is of the pattern seen in Kuchneotherium and Ttnodon. The ińterlocking mechanism and the type of occlusion ally Amphilestidae with Kuehneotheriidae, from which they differ in having lower molariforms with main cusps aligned and the dentary-squamosal jaw joint (double jaw joint in Kuehneotheńdae). The main cusps in upper molariforms M3-M5 of Gobiconodon, however, show incipient tńangular arrangement. The paper gives some support to Mills' idea on the therian affinities of the Amphilestidae, although it cannot be excluded that the characters that unite the two groups developed in parallel. Because of scanty material and arnbiguĘ we assign the Amphilestidae to order incertae sedis. Key words : Mammali4 .triconodonts', Amphilestidae, Kuehneotheriidae, Early Cretaceous, Mongolia. Zofia Kiel,an-Jaworowska [zkielnn@twarda,pan.pl], InsĘtut Paleobiologii PAN, ul. Twarda 5 I /5 5, PL-00-8 I 8 Warszawa, Poland. DemberĘin Dash7eveg, Geological Institute, Mongolian Academy of Sciences, Ulan Bator, Mongolia. Introduction Beliajeva et al. (1974) reportedthe discovery of Early Cretaceous mammals at the Khoboor locality (referred to also sometimes as Khovboor), in the Guchin Us Soinon (County), Gobi Desert, Mongolia.
    [Show full text]
  • Paleontological Discoveries in the Chorrillo Formation (Upper Campanian-Lower Maastrichtian, Upper Cretaceous), Santa Cruz Province, Patagonia, Argentina
    Rev. Mus. Argentino Cienc. Nat., n.s. 21(2): 217-293, 2019 ISSN 1514-5158 (impresa) ISSN 1853-0400 (en línea) Paleontological discoveries in the Chorrillo Formation (upper Campanian-lower Maastrichtian, Upper Cretaceous), Santa Cruz Province, Patagonia, Argentina Fernando. E. NOVAS1,2, Federico. L. AGNOLIN1,2,3, Sebastián ROZADILLA1,2, Alexis M. ARANCIAGA-ROLANDO1,2, Federico BRISSON-EGLI1,2, Matias J. MOTTA1,2, Mauricio CERRONI1,2, Martín D. EZCURRA2,5, Agustín G. MARTINELLI2,5, Julia S. D´ANGELO1,2, Gerardo ALVAREZ-HERRERA1, Adriel R. GENTIL1,2, Sergio BOGAN3, Nicolás R. CHIMENTO1,2, Jordi A. GARCÍA-MARSÀ1,2, Gastón LO COCO1,2, Sergio E. MIQUEL2,4, Fátima F. BRITO4, Ezequiel I. VERA2,6, 7, Valeria S. PEREZ LOINAZE2,6 , Mariela S. FERNÁNDEZ8 & Leonardo SALGADO2,9 1 Laboratorio de Anatomía Comparada y Evolución de los Vertebrados. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”, Avenida Ángel Gallardo 470, Buenos Aires C1405DJR, Argentina - fernovas@yahoo. com.ar. 2 Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina. 3 Fundación de Historia Natural “Felix de Azara”, Universidad Maimonides, Hidalgo 775, C1405BDB Buenos Aires, Argentina. 4 Laboratorio de Malacología terrestre. División Invertebrados Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”, Avenida Ángel Gallardo 470, Buenos Aires C1405DJR, Argentina. 5 Sección Paleontología de Vertebrados. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”, Avenida Ángel Gallardo 470, Buenos Aires C1405DJR, Argentina. 6 División Paleobotánica. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”, Avenida Ángel Gallardo 470, Buenos Aires C1405DJR, Argentina. 7 Área de Paleontología. Departamento de Geología, Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria (C1428EGA) Buenos Aires, Argentina. 8 Instituto de Investigaciones en Biodiversidad y Medioambiente (CONICET-INIBIOMA), Quintral 1250, 8400 San Carlos de Bariloche, Río Negro, Argentina.
    [Show full text]