Advertisement

Paläontologische Zeitschrift

, Volume 82, Issue 2, pp 209–229 | Cite as

Two new species of the side necked turtle genus,Bairdemys (Pleurodira, Podocnemididae), from the Miocene of Venezuela

  • Eugene S. Gaffney
  • Torsten M. Scheyer
  • Kenneth G. Johnson
  • Jean Bocquentin
  • Orangel A. Aguilera
Article

Abstract

The side-necked turtle genusBairdemys (Podocnemididae,Shweboemys Group) from the Miocene of Venezuela and Puerto Rico is revised, and four species are diagnosed on the basis of skull characters; two are de-scribed as new.B. hartsteini Gaffney & Wood, 2002, from the Cibao Formation of Puerto Rico, is characterized by a higher skull, with a straight labial ridge and a premaxillary notch;B. venezuelensis (Wood & Díaz de Gamero 1971), from the Urumaco Formation of Venezuela, is characterized by the absence of a premaxillary notch, a high anterior triturating surface convexity, a deep posterior triturating surface concavity, and a short pterygoid mid-line contact;B. sanchezi, new species, from the Urumaco Formation of Venezuela, is characterized by a very low anterior triturating surface convexity and shallow posterior triturating surface concavity, a premaxillary notch, small size, and extensive temporal and cheek emargination;B. winklerae, new species, from the Urumaco Formation of Venezuela, is characterized by an elongate, narrow snout, with a concave labial ridge, and no premaxillary notch. Based on osteological and bone histological results, an additional strongly crushed skull and associated cara-pace fragment of a previously undetermined podocnemidid from the Urumaco Formation of Venezuela can be further referred toPodocnemis or a closely related taxon — again underscoring the importance of this formation as one of the major fossil lagerstätten of turtles in South America.

Keywords

Pleurodires Podocnemididae Bairdemys Urumaco Fm Venezuela shell bone histology 

Zusammenfassung

Die Halswenderschildkröten der GattungBairdemys (Podocnemididae,Shweboemys-Gruppe) aus dem Miozän von Venezuela und Puerto Rico werden revidiert. Aufgrund von diagnostischen Schädelmerkmalen werden vier Arten unterschieden, inklusive zwei hierin neu beschriebener Arten.B. hartsteini Gaffney & Wood, 2002, aus der Cibao Formation, Puerto Rico, ist durch einen hohen Schädel, eine gerade Labialkante des Prämaxillare und eine Prämaxillarkerbe gekennzeichnet,B. venezuelensis (Wood & Diaz de Gamero 1971) aus der Urumaco-Formation Venezuelas durch das Fehlen einer Prämaxillarkerbe, eine hohe anteriore Konvexität und eine tiefe posteriore Konkavität der Kauflächen und einen kurzen Mittellinienkontakt der Pterygoide. Die hier neu beschriebeneB. sanchezi n. sp. aus der Urumaco-Formation, Venezuela, ist charakterisiert durch eine sehr niedrige anteriore Konvexität und eine flache posteriore Konkavität der Kauflächen, eine geringe Größe und starke Temporal- und Wangeneinbuchtungen, wogegenB. winklerae n. sp. aus der Urumaco Formation, Venezuela, durch eine verlängerte schmale Schnauze mit einer konkaven Labialkante charakterisiert ist. Durch osteologische und knochenhistologische Befunde lassen sich ein weiterer stark verdrückter Schädel sowie ein assoziiertes Panzerfragment einer bisher unbestimmten Podocnemidide der GattungPodocnemis oder deren unmittelbarer Verwandtschaft zuordnen. Dies unterstreicht wiederum die Bedeutung der Urumaco-Formation als eine der wichtigsten Lagerstätten fossiler Schildkröten in Südamerika.

Schlüsselwörter

Pleurodira Podocnemididae Bairdemys Urumaco-Formation Knochenhistologie des Schildkrötenpanzers Venezuela 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Aguilera, O.A. 2004. Tesoros Paleontologicos de Venezuela: Uru-maco, Patrimonio Natural de la Humanidad. — 148 p., Caracas (Arte).Google Scholar
  2. Cann, J. 1998. Australian Freshwater Turtles. — 292 p., Singapore (Beaumont Publishing).Google Scholar
  3. Cope, E.D. 1864. On the limits and relations of the Raniformes. — Proceedings of the Academy of Natural Sciences of Philadelphia16: 181–183.Google Scholar
  4. Cope, E.D. 1868. On the origin of genera. — Proceedings of the Academy of Natural Sciences of Philadelphia20: 242–300.Google Scholar
  5. Cozzuol, M.A. 2006. The Acre vertebrate fauna: age, diversity, and geography. — Journal of South American Earth Sciences21: 185–203.CrossRefGoogle Scholar
  6. Dalrymple, G.H. 1977. Intraspecific Variation in the cranial feeding mechanism of turtles of the genusTrionyx (Reptilia, Testudines, Trionychidae). — Journal of Herpetology11 (3): 255–285.CrossRefGoogle Scholar
  7. Díaz de Gamero, M.L. &Linares O. J. 1989. Estratigrafía y paleontología de la Formacíon Urumaco, del Mioceno Tardío de Falcón Noroccidental. — VII. Congreso Geológico Venezolano, Memorias1: 419–438.Google Scholar
  8. Díaz de Gamero, M.L. 1996. The changing course of the Orinoco River during the Neogene: a review. — Palaeogeography, Palaeoclimatology, Palaeoecology123: 385–402.CrossRefGoogle Scholar
  9. Gaffney, E.S. &Wood, R.C. 2002.Bairdemys, a new side-necked turtle (Pelomedusoides: Podocnemididae) from the Miocene of the Caribbean. — American Museum Novitates3359: 1–28.CrossRefGoogle Scholar
  10. Gaffney, E.S.;Tong, H. &Meylan, P. 2006. Evolution of the side-necked turtles: the families Bothremydidae, Euraxemydidae, and Araripemydidae. — Bulletin of the American Museum of Natural History300: 1–698.CrossRefGoogle Scholar
  11. Lindeman, P.V. 2000. Evolution of the relative width of the head and alveolar surfaces in map turtles (Testudines: Emydidae:Graptemys). — Biological Journal of the Linnean Society69: 549–576.Google Scholar
  12. Ministerio de Energía Y Minas. 1997. Léxico Estratigráfico de Venezuela (Tercera Edición). — Boletín de Geología12: 1–828.Google Scholar
  13. Sánchez-Villagra, M.R. &Aguilera, O.A. 2006. Neogene vertebrates from Urumaco, Falcón State, Venezuela: diversity and significance. — Journal of Systematic Palaeontology4 (3): 213–220.CrossRefGoogle Scholar
  14. Sánchez-Villagra, M.R. &Winkler J.D. 2006. Cranial Variation inBairdemys turtles (Podocnemididae: Miocene of the Caribbean region) and description of new material from Urumaco, Venezuela. — Journal of Systematic Palaeontology4 (3): 241–253.CrossRefGoogle Scholar
  15. Sänchez-Villagra, M.R.;Aguilera, O.A. &Horovitz, I. 2003. The anatomy of the world’s largest extinct rodent. — Science301: 1708–1710.CrossRefGoogle Scholar
  16. Sánchez-Villagra, M.R.;Burnham, R.J.;Campbell, D.C.;Feldmann, R.M.;Gaffney, E.S.;Kay, R.F.;Lozsán, R.;Purdy, R. &Thewissen, J.G.M. 2000. A new near-shore marine fauna and flora from the Early Neogene of northwestern Venezuela. — Journal of Paleontology74 (5): 957–968.CrossRefGoogle Scholar
  17. Sánchez-Villagra, M.R.;Asher, R.J.;Rincón, A.D.;Carlini, A.A.;Meylan, P. &Purdy, R.W. 2004. New faunal reports for the Cerro La Cruz locality (Lower Miocene), north-western Venezuela. — In:Sänchez-Villagra, M.R. &Clack, J.A., eds., Fossils of the Miocene Castillo Formation, Venezuela: Contributions on Neotropicat Palaeontology. — Special Papers in Palaeontology71: 105–112.Google Scholar
  18. Scheyer, T.M. &Sánchez-Villagra, M.R. 2007. Carapace bone histology in the giant pleurodiran turtleStupendemys geographicus: phylogeny and function. — Acta Palaeontologica Polonica52 (1): 137–154.Google Scholar
  19. Scheyer, T.M.;Sander, P.M.;Joyce, W.G.;Böhme, W. &Witzel, U. 2007. A plywood structure in the shell of fossil and living soft-shelled turtles (Trionychidae) and its evolutionary implications. — Organisms, Diversity & Evolution7 (2): 136–144.CrossRefGoogle Scholar
  20. Winkler, J.D. &Sänchez-Villagra, M.R. 2006. A nesting site and egg morphology of a Miocene turtle from Urumaco, Venezuela: direct evidence of marine adaptations in a pelomedusoides. — Palaeontology49: 641–646.CrossRefGoogle Scholar
  21. Wood, R.c. &Díaz de Gamero, M.L. 1971.Podocnemis venezuelensis, a new fossil pelomedusid (Testudines, Pleurodira) from the Pliocene of Venezuela and a review of the history ofPodocnemis in South America. — Breviora405: 1–10.Google Scholar
  22. Wood, R.C. 1997. Turtles. — In:Kay, R.F.;Madden, R.H.;Cifelli, R.L. &Flynn, J.J., eds., Vertebrate Paleontology in the Neotro-pics: the Miocene Fauna of La Venta, Colombia: 155–170, Washington DC (Smithsonian Institution Press).Google Scholar

Copyright information

© E. Schweizerbart’sche Verlagsbuchhandlung 2008

Authors and Affiliations

  • Eugene S. Gaffney
    • 1
  • Torsten M. Scheyer
    • 2
  • Kenneth G. Johnson
    • 3
  • Jean Bocquentin
    • 4
  • Orangel A. Aguilera
    • 5
  1. 1.Division of PaleontologyAmerican Museum of Natural HistoryNew YorkUSA
  2. 2.Paläontologisches Institut und MuseumUniversität ZürichZürichSwitzerland
  3. 3.Department of PalaeontologyNatural History MuseumLondonUnited Kingdom
  4. 4.Laboratório de PaleontologiaUniversidade Federal do AcreBrasil
  5. 5.Centro de Investigaciones en Ciencias Básicas, Complejo Docente Los PerozosUniversidad Nacional Experimental Francisco de MirandaEstado FalcónVenezuela

Personalised recommendations