Skip to main content Skip to main navigation menu Skip to site footer
Article
Published: 2016-04-19

Morphological variation in the Brazilian Radiated Swamp Turtle Acanthochelys radiolata (Mikan, 1820) (Testudines: Chelidae)

Département de Géosciences, Université de Fribourg, Fribourg, 1700, Switzerland Departamento de Vertebrados, Museu Nacional, Universidade Federal do Rio de Janeiro, Quinta da Boa Vista, Rio de Janeiro, RJ, 20940-40, Brazil
Departamento de Zoologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Ilha do Fundão, Rio de Janeiro, RJ, 21941-902, Brazil
Departamento de Zoologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Ilha do Fundão, Rio de Janeiro, RJ, 21941-902, Brazil Departamento de Vertebrados, Museu Nacional, Universidade Federal do Rio de Janeiro, Quinta da Boa Vista, Rio de Janeiro, RJ, 20940-40, Brazil
Universidade Católica de Pernambuco, Rua do Príncipe 526, Boa Vista, Recife, PE, 50050-900, Brazil Departamento de Vertebrados, Museu Nacional, Universidade Federal do Rio de Janeiro, Quinta da Boa Vista, Rio de Janeiro, RJ, 20940-40, Brazil
geographic distribution morphology taxonomy turtles Reptilia Brazil

Abstract

The freshwater turtle Acanthochelys radiolata (Mikan, 1820) is endemic to the Atlantic Forest domain in Brazil and few studies have been done on the morphology, geographic variation and taxonomy of this species. In this paper we record the morphological variation, as well as sexual dimorphism and ontogenetic changes in A. radiolata throughout its distribution range. We analyzed 118 morphological characters from 41 specimens, both quantitative and qualitative, and performed statistical analyses to evaluate size and shape variation within our sample. Morphological analysis revealed that A. radiolata is a polymorphic species, especially regarding color and shape. Two color patterns were recognized for the carapace and three for the plastron. Diagnostic characteristics of the species, such as the rounded tubercles on the neck and the shallow dorsal sulcus between the 2nd and 4th vertebral scutes, varied considerably. Acanthochelys radiolata also showed a high level of ontogenetic variation characterized by a change on the color pattern of plastron and limbs starting from the 4th month of life. Sexual size dimorphism was observed for the first time on nine morphometric variables and females showed larger sizes than males. Based on these results we conclude that A. radiolata represents one single polymorphic species distributed in the lowlands of the Brazilian Atlantic Forest from the state of Alagoas to the state of Rio de Janeiro and the south of Minas Gerais state.

References

  1. Abell, R., Thieme, M.L., Revenga, C., Bryer, M., Kottelat, M., Bogutskaya, N., Coad, B., Mandrak, N., Contreras Balderas, S. Bussing, W., Stiassny, M.L.J., Skelton, P., Allen, G.R., Unmack, P., Naseka, A., Ng, R., Sindorf, N., Robertson, J., Armijo, E., Higgins, J.V., Heibel, T.J., Wikramanake, E., Olson, D., Lopez, H.L., Reis, R.E., Lundberg, J.G., Sabaj Perez, M.H. & Petry, P. (2008) Freshwater ecoregions of the world: a new map of biogeographic units for freshwater biodiversity conservation. BioScience, 58, 403–414.
    http://dx.doi.org/10.1641/B580507

    Bonin, F., Devaux, B. & Dupré A. (2006) Turtles of the world. The John Hopkins University Press, Baltimore, 416 pp.

    Boulenger, G.A. (1889) Catalogue of the chelonians, rynchocephalians, and crocodiles in the British Museum (Natural History). Taylor and Francis, London, 311 pp.

    Brasil, M.A., Horta, G.F., Neto, H.J.F., Barros, T.O. & Colli, G.R. (2011) Feeding ecology of Acanthochelys spixii (Testudines: Chelidae) in the Cerrado of Central Brazil. Chelonian Conservation and Biology, 10, 91–101.
    http://dx.doi.org/10.2744/CCB-0846.1

    Bujes, C.S., Molina, F.B. & Verrastro, L. (2011) Population characteristics of Trachemys dorbigni (Testudines, Emydidae) from Delta do Jacuí state park, Rio Grande do Sul, southern Brazil. South American Journal of Herpetology, 6, 27–34.
    http://dx.doi.org/10.2994/057.006.0104

    Cann, J. (1998) Australian freshwater turtles. Beaumont Publishing Pte Ltd, Singapore, 292 pp.

    Duméril, A.MC. & Bibron, G. (1835) Erpétologie générale ou histoire naturelle complète des reptiles. Tome second. Librairie Encyclopédique de Roret, Paris, 680 pp.

    Dustman, E. (2013) Sex identification in the Common Snapping turtle (Chelydra serpentina): a new technique and evaluation of previous methods. Herpetological Review, 44, 235–238.

    Ernst, C.H. & Barbour, R.W. (1989) Turtles of the World. Smithsonian Institution Press, Washington, D.C., 313 pp.

    Ernst, C.H. (1983) Geographic variation in the neotropical turtle, Platemys platycephala. Journal of Herpetology, 17, 345–355.
    http://dx.doi.org/10.2307/1563587

    Fritz, U. & Havaṧ P. (2007) Checklist of the chelonians of the world. Vertebrate Zoology, 57, 149–368.

    Gray, J.E. (1831) Synopsis Reptilium; or Short Descriptions of the Species of Reptiles. Part ICataphracta. Tortoises, Crocodiles, and Enaliosaurians. Treuttel, Wurz and Co, London, 85 pp.
    http://dx.doi.org/10.5962/bhl.title.4697

    Gray, J.E. (1844) Catalogue of the Tortoises, Crocodiles and Amphisbaenians in the Collection of the British Museum. Edward Newman, London, 80 pp.

    Heckenberger, M.J., Russell, J.C., Toney, J.R. & Schmidt, M.J. (2007) The legacy of cultural landscapes in the Brazilian Amazon: implications for biodiversity. Philosophical Transactions of the Royal Society, 362, 197–208.
    http://dx.doi.org/10.1098/rstb.2006.1979

    Huebinger, R.M., Bickham, J.W., Rhodin, A.G.J. & Mittermeier, R.A. (2013) Mitochondrial DNA corroborates taxonomy of the South American chelid turtles of the genera Platemys and Acanthochelys. Chelonian Conservation and Biology, 12, 168–171.
    http://dx.doi.org/10.2744/CCB-0800.1

    Iverson, J.B. (1992) A Revised Checklist with Distribution Maps of the Turtles of the World. Privately printed, Richmond, Indiana, 363 pp.

    Lovich, J.E. & Ernst, C.H. (1989) Variation in the plastral formulae of selected turtles with comments on taxonomic utility. Copeia, 304–318.
    http://dx.doi.org/10.2307/1445426

    Luederwalt, H. (1926) Os chelonios brasileiros com a lista das espécie do Museu Paulista. Revista Museu Paulista, 14, 403–470.

    McCord, W.P., Joseph-Ouni, M. & Lamar, W.W. (2001) A taxonomic reevaluation of Phrynops (Testudines: Chelidae) with the description of two new genera and a new species of Batrachemys. Revista de Biología Tropical, 49, 715–764.

    Mikan, J.C. (1820) Delectus Florae et Faunae Brasiliensis. Fasciculus Primus. Sumtibcs Auctoris, Typis Antonii Strauss, Vindobonae, 6 pp., 6 pls.

    Mocelin, M.A., Fernandes, R., Porto, M. & Fernandes, D.S. (2008) Reproductive biology and notes on natural history of the side-necked turtle Acanthochelys radiolata (Mikan, 1820) in captivity (Testudines: Chelidae). South American Journal of Herpetology, 3, 223–228.
    http://dx.doi.org/10.2994/1808-9798-3.3.223

    Molina, F.B. (1998) Comportamento e biologia reprodutiva dos cágados Phrynops geoffroanus, Acanthochelys radiolata e Acanthochelys spixii (Testudines, Chelidae) em cativeiro. Revista de Etologia, n. especial, 1998, 25–40.

    Moreira, J.R., Balestra, R.A.M., Freitas, F.O., Lustosa, A.P.G., Rosa, A.J.M., Sampaio, A.A. & Júnior, P.D.F. (2011) Podocnemis expansa (Giant South American River turtle) Nesting Range Expansion. Herpetological review, 42, 595–596.

    Myers, N., Mittermeier, R.A., Mittermeier, C.G., Fonseca, G.A.B. & Kent, J. (2000) Biodiversity hotspots for conservation priorities. Nature, 403, 853–858.
    http://dx.doi.org/10.1038/35002501

    Neto, H.J.F., Brasil, M.A., Horta, G.F., Barros, T.O., Falcon, G.B. & Colli, G.R. (2011) Demography of Acanthochelys spixii (Testudines: Chelidae) in the Brazilian Cerrado. Chelonian Conservation and Biology, 10, 82–90.
    http://dx.doi.org/10.2744/CCB-0876.1

    Nomura, H. (1993) A obra científica de Antenor Leitão de Carvalho (1910—1985). Revista Brasileira de Zoologia, 10, 545–552.
    http://dx.doi.org/10.1590/S0101-81751993000300023

    Rhodin, A.G.J., Rocha-e-Silva, R. & Mittermeier, R.A. (1984a) Distribution of the South American chelid turtles Platemys radiolata and P. spixii. Copeia, 780–786.
    http://dx.doi.org/10.2307/1445169

    Rhodin, A.G.J., Mittermeier, R.A. & Mcmorris, J.R. (1984b) Platemys macrocephala, a new species of chelid turtle from Central Bolivia and the Pantanal region of Brazil. Herpetologica, 40, 38–46.

    Rhodin, A.G.J,. Métrailler, S., Vinke, T., Vinke, S., Artner, H. & Mittermeier, R.A. (2009) Acanthochelys macrocephala (Rhodin, Mittermeier, and McMorris 1984) – Big-Headed Pantanal Swamp Turtle, Pantanal Swamp Turtle. Chelonian Research Monographs, 5, 040.1–040.8.

    Sneath, P.H.A. & Sokal, R.R. (1973) Numerical Taxonomy: the principles and practice of numerical classification. W.H.Freeman, San Francisco, 573 pp.

    Souza, F.L. (2004) Uma revisão sobre padrões de atividade, reprodução e alimentação de cágados brasileiros (Testudines, Chelidae). Phyllomedusa, 3, 15–27.
    http://dx.doi.org/10.11606/issn.2316-9079.v3i1p15-27

    Statsoft Inc. (2004) Statistica for Windows (Computer Program Manual). Statsoft Inc., Tulsa, Oklahoma.

    Stuckas, H., Gemel, R. & Fritz, U. (2013) One extinct turtle less: Pelusios seychellensis is not extinct, it never existed. PloS One, 8, e57116.
    http://dx.doi.org/10.1371/journal.pone.0057116

    TTWG [Van Dijk, P.P., Iverson, J.B., Shaffer, H.B., Bour, R. & Rhodin, A.G.J.] (2011) Turtles of the World, 2011 Update: Annotated Checklist of Taxonomy, Synonymy, Distribution, and Conservation Status. Chelonian Research Monographs, 5, 000.165–000.242.
    http://dx.doi.org/10.3854/crm.5.000.checklist.v4.2011

    TTWG [Van Dijk, P.P., Iverson, J.B., Rhodin, A.G.J., Shaffer, H.B. & Bour, R.] (2014) Turtles of the World, 7th Edition: Annotated Checklist of Taxonomy, Synonymy, Distribution with Maps, and Conservation Status. Chelonian Research Monographs, 5, 329–479.
    http://dx.doi.org/10.3854/crm.5.000.checklist.v7.2014

    Vinke, T., Vinke, S., Richard, R., Cabrera, M.R., Paszko, L., Marano, P. & Métrailler, S. (2011) Acanthochelys pallidipectoris (Freiberg 1945)—Chaco Side-Necked Turtle. Chelonian Research Monographs, 5, 065.1–065.7.

    Weitzman, S.H. & Menezes, N.A. (1989) George Sprague Myers (2/II/1905—4/XI/1985). Revista Brasileira de Zoologia, 6, 175–177.
    http://dx.doi.org/10.1590/S0101-81751989000100019

    Zawadzki, C.H., Birindelli, J.L.O. & Lima, F.C.T. (2008) A new pale-spotted species of Hypostomus Lacépède (Siluriformes: Loricariidae) from the rio Tocantins and rio Xingu basins in central Brazil. Neotropical Ichthyology, 6, 395–402.
    http://dx.doi.org/10.1590/s1679-62252008000300012

    Zar, J.H. (1999) Biostatistical Analysis. Prentice-Hall, New Jersey, 663 pp.

How to Cite

GARBIN, R. C., KARLGUTH, D. T., FERNANDES, D. S., & PINTO, R. R. (2016). Morphological variation in the Brazilian Radiated Swamp Turtle <em>Acanthochelys radiolata </em>(Mikan, 1820) (Testudines: Chelidae). Zootaxa, 4105(1), 45–64. https://doi.org/10.11646/zootaxa.4105.1.2