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New Pleistocene remains of megalonychid ground sloths (Xenarthra: Pilosa) from the intertropical Brazilian region

Published online by Cambridge University Press:  24 June 2016

Gerardo De Iuliis
Affiliation:
Department of Ecology and Evolutionary Biology, University of Toronto, 25 Harbord Street, Toronto, Ontario M5S 3G5, Canada; and Section of Palaeobiology, Department of Natural History, Royal Ontario Museum, 100 Queen’s Park Crescent, Toronto, Ontario M5S 2C6, Canada 〈gerry.deiuliis@utoronto.ca〉
Cástor Cartelle
Affiliation:
Pontifíca Universidade Católica de Minas Gerais (PUC Minas), Avenida Dom José Gaspar, 290 Coração Eucarístico, Belo Horizonte, Minas Gerais, Brazil 〈cartelle@pucminas.br〉
François Pujos
Affiliation:
Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales (IANIGLA), CCT-CONICET-Mendoza, Avda. Ruiz Leal s/n, Parque Gral. San Martín, 5500 Mendoza, Argentina 〈fpujos@mendoza-conicet.gov.ar〉

Abstract

The Pleistocene fossil sloth Australonyx aquae De Iuliis, Cartelle, and Pujos, 2009 (Mammalia, Xenarthra, Megalonychidae) was described from the intertropical region of Brazil. However, its mandible was not known and only cursory descriptions of the ear ossicles were included. The mandible was subsequently recognized among the remains originally collected from the type locality, and belongs to the holotype individual. As a particularly important skeletal element for specific recognition, it requires description to complement our understanding of this species. The ossicles, usually poorly represented in the fossil record, require further description to allow differentiation from those of other sloths. Comparisons of the mandible and ossicles are conducted with homologous elements of the contemporaneous and sympatric Ahytherium aureum Cartelle, De Iuliis, and Pujos, 2008, the only other megalonychid sloth known from intertropical Brazil, and reinforce the distinction between these two species detailed in their initial descriptions. Comparisons with other sloths (e.g., Acratocnus, Megalonyx, Neocnus) also reveal differences with Au. aquae in such features as form and size of the caniniform tooth, angular process, and mandibular condyle. Differences among the malleus and incus of Au. aquae and several species of other sloth clades reveal clade level distinctions among Megatheriidae, Nothrotheriidae, and Megalonychidae. A well-preserved skull from the Brazilian state of Rondônia is noted as probably belonging to Au. aquae. This skull cannot be assigned formally to this species because it is not deposited in a recognized institution, but it does extend considerably the known range of the species.

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Articles
Copyright
Copyright © 2016, The Paleontological Society 

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References

Anthony, H.E., 1916, Preliminary report on fossil mammals from Porto Rico, with descriptions of a new genus of ground sloth and two new genera of hystricomorph rodents: Annals of the New York Academy of Sciences, v. 27, p. 193203.CrossRefGoogle Scholar
Anthony, H.E., 1926, Mammals of Porto Rico, living and extinct – Rodentia and Edentata: New York Academy of Sciences, Scientific Survey of Porto Rico and the Virgin Islands, v. 9, p. 97243.Google Scholar
Arredondo, O., 1961, Descripciones preliminares de dos nuevos géneros y especies de edentados del Pleistoceno cubano: Boletín del Grupo de Exploraciones Científicas, v. 1, p. 1940.Google Scholar
Burmeister, H., 1886, Atlas de la description physique de la République Argentine contenant des vues pittoresques et des figures d’Histoire Naturelle, (2) Mammifères: Osteologie der Gravigraden oder Riesen-Faulthiere, p. 65125.Google Scholar
Cartelle, C., 1992, Os Edentata e megamamíferos herbívoros da Toca das Ossos (Ourolândia, BA), Belo Horizonte: Unpublished Ph.D dissertation, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil, 700 p.Google Scholar
Cartelle, C., 2002, Peter W. Lund a naturalist of several sciences: Lundiana, v. 3, p. 8385.CrossRefGoogle Scholar
Cartelle, C., De Iuliis, G., and Pujos, F., 2008, A new species of Megalonychidae (Mammalia, Xenarthra) from the Quaternary of Poço Azul (Bahia, Brazil): Comptes Rendus Palevol, v. 7, p. 335346.Google Scholar
Cartelle, C., De Iuliis, G., and Lopes, R., 2009, Systematic revision of tropical Brazilian scelidotherine sloths (Xenarthra, Mylodontoidea): Journal of Vertebrate Paleontology, v. 29, p. 555566.Google Scholar
Cartelle, C., and Fonseca, J.S., 1983, Contribuição ao melhor conhecimento da pequena preguiça terrícola Nothrotherium maquinense (Lund) Lydekker, 1889: Lundiana, v. 2, p. 1148.Google Scholar
Cope, E.D., 1889, The Edentata of North America: American Naturalist, v. 23, p. 657664.Google Scholar
De Iuliis, G., 1996, A systematic review of the Megatheriinae (Mammalia: Xenarthra: Megatheriidae): Unpublished Ph.D dissertation, University of Toronto, Toronto, Canada, 781 p.Google Scholar
De Iuliis, G., Pujos, F., and Cartelle, C., 2009, A new ground sloth (Mammalia: Xenarthra) from the Quaternary of Brazil: Compte Rendus Palevol, v. 8, p. 705715.Google Scholar
De Iuliis, G., Pujos, F., Toledo, N., Bargo, M.S., and Vizcaíno, S.F., 2014, Eucholoeops Ameghino, 1887 (Xenarthra, Tardigrada, Megalonychidae) from the Santa Cruz Formation, Argentine Patagonia: implications for the systematics of santacrucian sloths: Geodiversitas, v. 36, p. 209255.CrossRefGoogle Scholar
Esteban, G.I., 1996, Revisión de los Mylodontinae cuaternarios (Edentata-Tardigrada) de Argentina, Bolivia y Uruguay. Sistemática, filogenia, paleobiología, paleozoogeografía y paleoecología: Unpublished Ph.D dissertation, Universidad Nacional de Tucumán, Facultad de Ciencias Naturales e Instituto Miguel Lillo, Tucumán, Argentina, 314 p.Google Scholar
Flower, W.H., 1883, On the arrangement of the Orders and Families of existing Mammalia: Proceedings of the Zoological Society of London, no. 1883, p. 178186.Google Scholar
Gaudin, T.J., 2011, On the osteology of the auditory region and orbital wall in the extinct West Indian sloth genus Neocnus Arredondo, 1961 (Placentalia, Xenarthra, Megalonychidae): Annals of the Carnegie Museum, v. 80, p. 528.Google Scholar
Gervais, P., 1855, Animaux nouveaux ou rares recueillis pendant l’expédition dans les parties centrales de l’Amérique du Sud, de Rio de Janeiro à Lima, et de Lima au Parana: Paris, P. Bertrand, ed., v. 1, 465 p.Google Scholar
Gervais, P., 1874, Lestodon trigonidens et Valgipes deformis : Journal de Zoologie, v. 3, p. 162164.Google Scholar
Guérin, C., and Faure, M., 2006, Diversité mammalienne au Pléistocene supérieur- Holocène ancien dans la région du Parc National Serra da Capivara (SE du Piaui, Brésil). II Simpósio Internacional “O povoamento das Américas”: FUMDAMentos, v. 7, 7992.Google Scholar
Guérin, C., Faure, M., Simões, P.R., Hugueney, M., and Mourer-Chauviré, C., 2002, Toca da Janela da Barra do Antonião, São Raimundo Nonato, PI - Rica fauna pleistocênica e registro da Pré-história brasileira, in Schobbenhaus, C., Campos, D.A., Queiroz, E.T., Winge, M., and Berbert-Born, M.C.L., eds., Sítios Geológicos e Paleontológicos do Brasil: Comissão Brasileira de Sítios Geológicos e Paleobiológicos, v. 1, p. 131137.Google Scholar
Harlan, R., 1825, Fauna Americana: being a description of the mammiferous animals inhabitating North America: Finley, A., ed., Philadelphia, 201 p.Google Scholar
Hoffstetter, R., 1954, Les gravigrades (Edentés Xénarthres) des cavernes de Lagoa Santa (Minas Gerais, Brésil): Annales des Sciences Naturelles comprenant la Zoologie, v. 16, p. 741764.Google Scholar
Latham, J., and Davies, H., 1795, Faunula indica, in Forster, J.R., ed., Zoologia Indica, 2d ed. Halle, p. 138.Google Scholar
Leidy, J., 1868, Notice of some vertebrate remains from the West Indian islands: Proceedings of the Academy of Natural Sciences of Philadelphia, v. 20, p. 178180.Google Scholar
Linnaeus, C., 1758, Systema Naturae per Regna tria Naturae, secundum Classes, Ordines, Genera, Species, cum Characteribus, Differentis, Synonymis, Locis, 10th ed., Stockholm, Sweden, Laurentii, Slavi, 824 p.Google Scholar
Lund, P.W., 1839, Blik paa Brasiliens Dyreverden för Sidste Jordomvaeltning. Anden Afhandling: Patterdyrene: Det Kongelige Danske Videnskabernes Selskbas Naturvidenskabelige og Mathematiske Afhandlinger, v. 8, p. 61144.Google Scholar
Lund, P.W., 1840, Blik paa Brasiliens Dyreverden för Sidste Jordomvaeltning, Tredie Afhandling, Forsaettelse af Pattedyrene: Det Kongelige Danske Videnskabernes Selskbas Naturvidenskabelige og Mathematiske Afhandlinger, v. 8, p. 217272.Google Scholar
Lund, P.W., 1842, Blik paa Brasiliens Dyreverden för Sidste Jordomvaeltning, Tredie Afhandling, Forsaettelse af Pattedyrene: Det Kongelige Danske Videnskabernes Selskbas Naturvidenskabelige og Mathematiske Afhandlinger, v. 9, p. 137208.Google Scholar
Lund, P.W., 1846, Meddelelse af Det Udbytte de i 1844 undersögte knoglehuler Have afgivet til hundskaben om Brasiliens Dyreverden för Sidste Jordomvaeltning: Det Kongelige Danske Videnskabernes Selskbas Naturvidenskabelige og Mathematiske Afhandlinger, v. 12, p. 194.Google Scholar
Lydekker, R., 1889, Nototherium and Zygomaturus : Annals and Magazine of Natural History, v. 4, p. 149152.CrossRefGoogle Scholar
MacPhee, R.D.E., White, J.L., and Woods, C.A., 2000, New megalonychid sloths (Phyllophaga, Xenarthra) from the Quaternary of Hispaniola: American Museum Novitates, no. 3303, p. 132.Google Scholar
McDonald, H.G., 1987, A systematic review of the Plio-Pleistocene scelidotherine ground sloths (Mammalia: Xenarthra: Mylodontidae): Unpublished Ph.D dissertation, Toronto, University of Toronto, Canada, 478 p.Google Scholar
McDonald, H.G., 2006, Sexual dimorphism in the skull of Harlan’s ground sloth: Contributions in Science, no. 510, p. 19.Google Scholar
Miller, G.S., 1929, A second collection of mammals from caves near St. Michel, Haiti: Smithsonian Miscellaneous Collections, v. 1, p. 130.Google Scholar
Naples, V.L., 1982, Cranial osteology and function in the tree sloths, Bradypus and Choloepus : American Museum Novitates, no. 2739, p. 141.Google Scholar
Patterson, B., Turnbull, W.D., Segall, W., and Gaudin, T.J., 1992, The ear region in Xenarthrans (=Edentata : Mammalia), part II, Pilosa (Sloths, Anteaters), Palaeanodonts, and a Miscellany: Fieldania, no. 1438, p. 178.Google Scholar
Paula Couto, C. de, 1980, Fossil Pleistocene to sub-recent mammals from northeastern Brazil: I. Edentata, Megalonychidae: Anais da Academia Brasileira de Ciências, v. 52, p. 144151.Google Scholar
Winge, H., 1915, Jordgundne og nulevende Gumlere (Edentata) fra Lagoa Santa, Minas Gerais, Brasilien: Medudsigt over gumlernes indbyrdes slaegtskab: E Museo Lundii, v. 3, p. 1321.Google Scholar