Skip to main content Skip to main navigation menu Skip to site footer
Type: Article
Published: 2019-08-06
Page range: 445–470
Abstract views: 119
PDF downloaded: 6

Chance, luck and a fortunate finding: a new species of watersnake of the genus Helicops Wagler, 1828 (Serpentes: Xenodontinae), from the Brazilian Pantanal wetlands

Departamento de Biologia e Zoologia, Instituto de Biociências, Universidade Federal de Mato Grosso, Av. Fernando Corrêa da Costa, 2367, 78060-900, Cuiabá, Mato Grosso, Brazil. Departamento de Zoologia, Centro de Biociências, Universidade Federal de Pernambuco, Avenida Professor Moraes Rego, 1235, Cidade Universitária, 50670-901, Recife, Pernambuco, Brazil.
Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, Travessa 14, P.O. Box 11.461, 05508-090, São Paulo, São Paulo, Brazil.
Departamento de Zoologia, Centro de Biociências, Universidade Federal de Pernambuco, Avenida Professor Moraes Rego, 1235, Cidade Universitária, 50670-901, Recife, Pernambuco, Brazil.
Centro de Biodiversidade, Instituto de Biociências, Universidade Federal de Mato Grosso, Av. Fernando Corrêa da Costa, 2367, 78060-900, Cuiabá, Mato Grosso, Brazil
Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, Travessa 14, P.O. Box 11.461, 05508-090, São Paulo, São Paulo, Brazil
Departamento de Biologia e Zoologia, Instituto de Biociências, Universidade Federal de Mato Grosso, Av. Fernando Corrêa da Costa, 2367, 78060-900, Cuiabá, Mato Grosso, Brazil. Setor de Herpetologia, Departamento de Vertebrados, Museu Nacional, Universidade Federal do Rio de Janeiro, Quinta da Boa Vista, São Cristovão, 20940-040, Rio de Janeiro, Rio de Janeiro, Brazil.
Departamento de Biologia e Zoologia, Instituto de Biociências, Universidade Federal de Mato Grosso, Av. Fernando Corrêa da Costa, 2367, 78060-900, Cuiabá, Mato Grosso, Brazil. Setor de Herpetologia, Departamento de Vertebrados, Museu Nacional, Universidade Federal do Rio de Janeiro, Quinta da Boa Vista, São Cristovão, 20940-040, Rio de Janeiro, Rio de Janeiro, Brazil.
Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, Travessa 14, P.O. Box 11.461, 05508-090, São Paulo, São Paulo, Brazil.
Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, Travessa 14, P.O. Box 11.461, 05508-090, São Paulo, São Paulo, Brazil.
Departamento de Biologia e Zoologia, Instituto de Biociências, Universidade Federal de Mato Grosso, Av. Fernando Corrêa da Costa, 2367, 78060-900, Cuiabá, Mato Grosso, Brazil.
Reptilia Hydropsini taxonomy color pattern molecular phylogeny distributional patterns

Abstract

We describe a new watersnake of the genus Helicops based on a single specimen found in the northern limit of the Brazilian Pantanal. Immediately after collection, the unique features of color pattern and head proportions prevented us to attribute this specimen to any other congener. Further comparisons revealed that the combination of entire nasal scales, a distinctively acuminate snout, high dorsal and supralabial counts, as well as a dorsal pattern with chain-like spot rows and a venter with vivid and peculiar orange markings confirmed that the specimen represented a new species. Molecular data supported our morphological conclusion recovering the new species deeply nested within Helicops terminals, sister to a clade composed by H. carinicaudus and H. nentur. Our discovery represents a rare instance of a snake species restricted to the Brazilian Pantanal, but we refrain from considering it a Pantanal endemic until further records allow more considerations on distributional patterns.

 

References

  1. Amaral, A. (1921) Contribuição para o conhecimento dos ofidios do Brazil. Parte I. Quatro novas espécies de serpentes brasileiras. Memórias do Instituto Butantan, 1, 1–37.

    https://doi.org/10.5962/bhl.title.10927

    Amaral, A. (1925) Ophidios de Matto Grosso (Contribuição II para o conhecimento dos ophidios do Brasil). Commissão de Linhas Telegraphicas Estratégicas de Matto Grosso ao Amazonas, Publicação 84, Anexo 5, História Natural, Zoologia, 1–29.

    Amaral, A. (1938) Estudos sobre ophidios neotropicos 34. Novas notas sobre a fauna da Colombia e descripção de uma espécie nova de colubrideo aglypho. Memórias do Instituto Butantan, 11 (1937), 232–240.

    Amaral, A. (1950) Two new South American Lizards. Copeia, 4, 281–284.

    https://doi.org/10.2307/1437908

    Ávila, R.W., Ferreira, V.L. & Arruda, J.A.O. (2006) Natural history of the South American water snake Helicops leopardinus (Colubridae: Hydropsini) in the Pantanal, Central Brasil. Journal of Herpetology, 40, 274–279.

    https://doi.org/10.1670/113-05N.1

    Bailey, J.R. (1967) The synthetic approach to colubrid classification. Herpetologica, 23, 155–161

    Bergna, S. & Alvarez,B. 1993. Descripción de una nueva especie de Thamnodynastes (Reptilia: Serpentes, Colubridae) del Nordeste Argentino. Facena, 10, 5–18

    Braz, H.B., Scartozzoni, R.R. & Almeida-Santos, S.M. (2016) Reproductive modes of the South American water snakes: a study system for the evolution of viviparity in squamate reptiles. Zoologischer Anzeiger, 263, 33–44.

    http://dx.doi.org/10.1016/j.jcz.2016.04.003

    Braz, H.B, Almeida-Santos, S.M., Murphy, C.R. & Thompson, M.B. (2018) Uterine and eggshell modifications associated with the evolution of viviparity in South American water snakes (Helicops spp.). Journal of Experimental Zoology B Molecular and Developmental Evolution, 330, 1–16.

    https://doi.org/10.1002/jez.b.22800

    Cope, E.D. (1862) Synopsis of the species of Holcosus and Ameiva, with diagnoses of new West Indian and South American Colubridae. Proceedings of the Academy of Natural Sciences of Philadelphia, 14, 60–82.

    Costa, H.C., Santana, D.J., Leal, F., Koroiva, R. & Garcia, P.C.A. (2016) A new species of Helicops (Serpentes: Dipsadidae: Hydropsini) from Southeastern Brazil. Herpetologica, 72, 157–166.

    https://doi.org/10.1655/HERPETOLOGICA-D-15-00059

    Cracraft, J. (1983) Species concepts and speciation analysis. In: Johnston, R.F. (Ed.), Current Ornithology. Springer, Boston, MA, 1, pp. 159–187.

    https://doi.org/10.1007/978-1-4615-6781-3_6

    Cruz-da-Silva, R.C., Freitas, M.A. & Abegg, A.D. (2018) A remarkable specimen of the genus Anilius (Serpentes: Aniliidae): rare colour aberration or a new species? Herpetology Notes, 11, pp. 161–165.

    Cunha, C.N. & Junk, W.J. (2009) Landscape units of the Pantanal: structure, function, and human use. In: Junk, W.J., Silva, C.J., Cunha, C.N. & Wantzen, K.M. (Eds.), The Pantanal: Ecology, Biodiversity and Sustainable Management of a Large Seasonal Wetland. Pensoft, Moscow, pp. 301–326.

    Cuvier, G. (1817) Le règne animal distribué d’après son organisation, pour servir de base a l’historire naturelle des animaux et d’introduction a l’anatomie comparée. Les reptiles, les poissons, les mollusques et les annélides. Tome 2. Déterville, Paris, 532 pp.

    https://doi.org/10.5962/bhl.title.49223

    Darriba, D., Taboada, G.L., Doallo, R. & Posada, D. (2012) jModel-Test 2: more models, new heuristics and parallel computing. Nature Methods, 9, 772–772.

    https://doi.org/10.1038/nmeth.2109

    Daudin, F.M. (1802) Histoire Naturelle, Générale et Particulière des Reptiles; ouvrage faisant suit à l’Histoire naturell générale et particulière, composée par Leclerc de Buffon; et rédigee par C.S. Sonnini, membre de plusieurs sociétés savantes. Tome 2. F. Dufart, Paris, 432 pp.

    https://doi.org/10.5962/bhl.title.60678

    Dowling, H.G. (1951) A proposed standard system of counting ventral in snakes. British Journal of Herpetology, 1, 97–99.

    https://doi.org/10.2307/1437542

    Dowling, H.G. (1975) A provisional classification of snakes. Yearbook of Herpetology, 1, 167–170.

    Dowling, H.G. & Savage, J.M. (1960) A guide to the snake hemipenis: a survey of basic structure and systematic characteristics. Zoologica, 45, 17–28.

    Duméril, A.M.C., Bibron, G. & Duméril, A. (1854) Érpetologie Générale ou Histoire Naturelle Complète des Reptiles. Tome 7. Librairie Encyclopédique de Roret, Paris, 1536 pp.

    https://doi.org/10.5962/bhl.title.112278

    Entiauspe-Neto, O.M., Lema, T. & Beconi, H.E.C. (2014) Apostolepis intermedia Koslowsky, 1898 (Serpentes: Xenodontinae: Elapomorphini): first records for Paraguay. Check List, 10 (3), 600–601.

    https://doi.org/10.15560/10.3.600

    Ferreira, V.L., Terra, J.S., Piatti, L., Strüssmann, C., Delatorre, M., Béda, A.F., Kawashita-Ribeiro, R.A., Landgref-Filho, P., Aoki, C., Campos, Z., Souza, F.L., Ávila, R.W., Duleba, S., Martins, K.S., Albuquerque, N.R. & Santa Rita, P.H. (2017) Répteis do Mato Grosso do Sul, Brasil. Iheringia, Série Zoologia, 107, 1–13.

    https://doi.org/10.1590/1678-4766e2017153

    Fetzner, S. (1999) Bioconversion of pyrimidine by resting cells of quinoline degrading bacteria. FEMS Microbiology Letters, 176, 291–299.

    https://doi.org/10.1111/j.1574-6968.1999.tb13675.x

    Frota, J.G. (2005) Nova espécie de Helicops Wagler, 1830 (Serpentes, Colubridae) do Rio Tapajós, Amazônia, Brasil. Phyllomedusa, 4, 61–68.

    https://doi.org/10.11606/issn.2316-9079.v4i1p61-67

    Fitzinger, L.J. (1826a) Neue Classification der Reptilien nach ihren Natürlichen Verwandtschaften. Nebst einer Verwandtschafts-Tafel und einem Verzeichnisse der Reptilien-Sammlung des K. K. zoologischen Museums zu Wien. J. G. Huebner, Viena, 66 pp.

    https://doi.org/10.5962/bhl.title.4683

    Godinho, R., Crespo, E.G., Ferrand, N. & Harris, D.J. (2005) Phylogeny and evolution of the green lizards, Lacerta spp. (Squamata: Lacertidae) based on mitochondrial and nuclear DNA sequences. Amphibia-Reptilia, 26, 271–285.

    https://doi.org/10.1163/156853805774408667

    Grazziotin, F.G., Zaher, H., Murphy, R.W., Scrocchi, G., Benavides, M.A., Zhang, Y. & Bonato, S.L. (2012) Molecular phylogeny of the New World Dipsadidae (Serpentes: Colubroidea): a reappraisal. Cladistics, 1, 1–23.

    https://doi.org/10.1111/j.1096-0031.2012.00393.x

    Gray, J.E. (1849) Catalogue of the Specimens of Snakes in the Collection of the British Museum. Trustees of the British Museum (Natural History), London, 125 pp.

    https://doi.org/10.5962/bhl.title.14873

    Griffin, L.E. (1916) A catalog of the ophidia from South America at present (June, 1916) contained in the Carnegie Museum with descriptions of some new species. Memoirs of the Carnegie Museum, 7, 163–228.

    https://doi.org/10.5962/bhl.title.43279

    Günther, A. (1861) On the ophidian genus Helicops. Annals and Magazine of Natural History, Series 3, 7, 425–428.

    Hamilton, S.K., Sippel, S.J. & Melack, J.M. (1996) Inundation patterns in the Pantanal wetland of South America determined from passive microwave remote sensing. Archiv fur Hydrobiologie, 137 (1), 1–23.

    Harvey, M.B. & Embert, D. (2008) Review of Bolivian Dipsas (Serpentes: Colubridae), with comments on other South American species. Herpetological Monographs, 22, 54–105.

    https://doi.org/10.1655/07-023.1

    Herrmann, J. (1804) Observationes Zoologicae quibus novae complures aliaeque animalium species, describuntur et illustrantur (opus posthumum) edidit Fridericus Ludovicus Hammer. Amandum Koenig, Paris, 332 pp.

    https://doi.org/10.5962/bhl.title.13456

    International Commission on Zoological Nomenclature [ICZN] (1999) International Code of Zoological Nomenclature. 4th Edition. International Trust for Zoological Nomenclature, London, 156 pp.

    Jan, G. (1863) Elenco Sistematico degli Ofidi Descritti e Designati per l’Iconografia Generale. Tipografia A. Lombardi, Milano, 143 pp.

    https://doi.org/10.5962/bhl.title.106683

    Jan, G. (1865) Enumerazione sistematica degli ofidi appartenenti al gruppo Potamophilidae. Archivio per la Zoologia, l’Anatomia et la Fisiologia, 3 (2), 201–265.

    https://doi.org/10.5962/bhl.title.52252

    Junk, W.J., Cunha, C.N., Wantzen, K.M., Peterman, P., Strüssmann, C., Marques, M.I. & Adis, J. (2006) Biodiversity and its conservation in the Pantanal of Mato Grosso, Brazil. Aquatic Sciences, 68, 278–309.

    https://doi.org/10.1007/s00027-006-0851-4

    Koslowsky, J. (1898) Ofidios de Matto-Grosso (Brasil). Revista del Museo de La Plata, 8, 25–32.

    Kawashita-Ribeiro, R.A., Ávila, R.W. & Morais, D.H. (2013) A new snake of the genus Helicops Wagler, 1830 (Dipsadidae, Xenodontinae) from Brazil. Herpetologica, 69, 80–90.

    https://doi.org/10.1655/HERPETOLOGICA-D-12-00013

    Kumar, S., Stecher, G. & Tamura K. (2016) MEGA7: Molecular Evolutionary Genetics Analysis Version 7.0 for Bigger Datasets. Molecular Biology Evolution, 33, 1870–1874.

    https://doi.org/10.1093/molbev/msw054

    Leaché, A.D. & Reeder, T.W. (2002) Molecular systematics of the Eastern Fence Lizard (Sceloporus undulatus): a comparison of Parsimony, Likelihood, and Bayesian approaches. Systematic Biology, 51, 44–68.

    https://doi.org/10.1080/106351502753475871

    Lema, T., Vieira, M.I. & Araújo, M.L. (1984) Fauna reptiliana do norte da Grande Porto Alegre, Rio Grande do Sul, Brasil. Revista Brasileira de Zoologia, 2, 203–227.

    http://dx.doi.org/10.1590/S0101-81751983000400002

    Leviton, A.E., Gibbs, R.H, Heal, E. & Dawson, C.E. (1985) Standards in herpetology and ichthyology: Part I. Standard symbolic codes for institutional resource collections in herpetology and ichthyology. Copeia, 3, 802–832.

    Lima, F.C.T. & Ribeiro, A.C. (2011) Continental-scale tectonic controls of biogeography and ecology. In: Albert, J.S. & Reis, R.E. (Eds.), Historical Biogeography of Neotropical Freshwater Fishes. University of California Press, Berkeley and Los Angeles, pp. 145–164.

    https://doi.org/10.1525/california/9780520268685.003.0009

    Linnaeus, C. (1758) Systema Naturae per regna tria naturae, secundum clases, ordines, genera, species, cum characteribus, differentis synonymis loci. Tomus I. Holmiae, Laurentii Salvii, 824 pp.

    https://doi.org/10.5962/bhl.title.542

    Manzani, P.R. & Abe, A.S. (1988) Sobre dois novos métodos de preparo do hemipenis de serpentes. Memorias do Instituto Butantan, 50, 15–20.

    Marques, O.A.V., Eterovic, A., Strüssmann, C. & Sazima, I. (2005) Serpentes do Pantanal: Guia ilustrado. Holos. Ribeirão Preto, 179 pp.

    Miller, M.A., Pfeiffer, W. & Schwartz, T. (2010) Creating the CIPRES science gateway for inference of large phylogenetic trees. In: Proceedings of the Gateway Computing Environments Workshop (GCE). IEEE, New Orleans, LA, pp. 1–8.

    https://doi.org/10.1109/GCE.2010.5676129

    Noonan, B.P. & Chippindale, P.T. (2006) Dispersal and vicariance: the complex evolutionary history of boid snakes. Molecular Phylogenetic and Evolution, 40, 347–358.

    https://doi.org/10.1016/j.ympev.2006.03.010

    Nunes, P.M.S., Fouquet, A., Curcio, F.F., Kok, P.J.R. & Rodrigues, M.T. (2012) Cryptic species in Iphisa elegans Gray, 1851 (Squamata: Gymnophthalmidae) revealed by hemipenial morphology and molecular data. Zoological Journal of the Linnean Society, 166, 361–376.

    https://doi.org/10.1111/j.1096-3642.2012.00846.x

    Nunes, P.M.S., Curcio, F.F., Roscito, J.G. & Rodrigues, M.T. (2014) Are hemipenial spines related to limb reduction? A spiny discussion focused on gymnophthalmid lizards (Squamata: Gymnophthalmidae). The Anatomical Record, 297, 482–495.

    https://doi.org/10.1002/ar.22876

    Padial, J.M., Miralles, A., De la Riva, I. & Vences, M. (2010) The integrative future of taxonomy. Frontiers in Zoology, 7, 1–14.

    https://doi.org/10.1186/1742-9994-7-16

    Palumbi, S.R. (1996) Nucleic Acids II: The Polymerase Chain Reaction. In: Hillis, D.M., Moritz, C. & Mable, B.K. (Eds.), Molecular Systematics. 2nd Edition. Sinauer Associates, Sunderland, MA, pp. 205–247.

    Paynter Jr., R.A. & Traylor Jr., M.A. (1991) Ornithological Gazetteer of Brazil. Vols. 1 & 2. Bird Department, Museum of Comparative Zoology, Harvard University, Cambridge. I + vii + 788 pp.

    https://doi.org/10.5962/bhl.title.14635

    Pesantes, O.S. (1994). A method for preparing the hemipenis of preserved snakes. Journal of Herpetology, 28, 93–95.

    https://doi.org/10.2307/1564686

    Peters, J.A. & Orejas-Miranda, B. (1970) Catalogue of the Neotropical Squamata. Part I. Snakes. United States National Museum Bulletin, 297, 1–347.

    https://doi.org/10.5479/si.03629236.297.1

    Pyron, R.A., Burbrink, F.T. & Wiens, J.J. (2013) A phylogeny and revised classification of Squamata, including 4161 species of lizards and snakes. BMC Evolutionary Biology, 13, 93.

    https://doi.org/10.1186/1471-2148-13-93

    QGIS Development Team (2016) QGIS Geographic Information System. Open Source Geospatial Foundation Project. Available from: http://qgis.osgeo.org (accessed 6 June 2018)

    Ronquist, F., Teslenko, M., van der Mark, P., Ayres, D.L., Darling, A., Höhna, S., Larget, B., Liu, L., Suchard, M.A. & Huelsenbeck, J.P. (2012) MrBayes 3.2: efficient bayesian phylogenetic inference and model choice across a large model pace. Systematic Biology, 61, 539–542.

    https://doi.org/10.1093/sysbio/sys029

    Rossman, D.A. (1976) Revision of the South American colubrid snakes of the Helicops pastazae complex. Occasional Papers of the Museum of Zoology, Louisiana State University, 50, 1–15.

    Rossman, D.A. & Dixon, J.R. (1975) A new colubrid snake of the genus Helicops from Peru. Herpetologica, 31, 412–414.

    Roux, J. (1910) Eine neue Helicops-Art aus Brasilien. Zoologischer Anzeiger, 36, 439–440.

    Sabaj, M.H. (2016) Standard symbolic codes for institutional resource collections in herpetology and ichthyology: an online reference. Version 6.5 (16 August 2016). American Society of Ichthyologists and Herpetologists, Washington, D.C. Available from: http://www.asih.org/ (accessed 9 July 2018)

    Schlegel, H. (1837) Essai sur la physionomie des serpens. Partie descriptive: Vol. 2. J. Kips, J. Hz. & W.P. Van Stockum, La Haye, 606 pp.

    https://doi.org/10.5962/bhl.title.4273

    Shreve, B. (1934) Notes on Ecuadorian Snakes. Occasional papers of the Boston Society of Natural History, 8, 125–131.

    Sick, H. (1997) Ornitologia brasileira. Editora Nova Fronteira, Rio de Janeiro, 862 pp.

    Spix, J.B. (1824) Serpentum brasiliensium species novae ou histoire naturelle des espèces nouvelles de serpens, recueillies et observées pendant le voyage dans l’intérieur du Brésil dans les années 1817, 1818, 1819, 1820. Exécuté par ordre de sa majesté le Roi de Bavière. Typis F. S. Hübschmanni, Monachii, viii pp.

    https://doi.org/10.5962/bhl.title.4269

    Stamatakis, A. (2014) RAxML Version 8: A tool for phylogenetic analysis and post-analysis of large phylogenies. Bioinformatics, 30, 1312–1313.

    https://doi.org/10.1093/bioinformatics/btu033

    Strüssmann, C. & Sazima, I. (1993) The snake assemblage of the Pantanal at Poconé, western Brazil: faunal composition and ecological summary. Studies on Neotropical Fauna and Environment, 28, 157–168.

    https://doi.org/10.1080/01650529309360900

    Strüssmann, C. (2000) Herpetofauna. In: Alho, C.J.R., Conceição, P.N., Constantino, R., Schlemmermeyer, T., Strüssmann, C., Vasconcellos, L.A.S., Oliveira, D.M.M. & and M. Schneider (Orgs.), Fauna Silvestre da Região do Rio Manso, MT. Ministério do Meio Ambiente/Edições IBAMA/Centrais Elétricas do Norte do Brasil, Brasília, pp. 153–189.

    Strüssmann, C. (2003) Herpetofauna. In: Cleber J.R. & Alho. C.J.R. (Org.), Conservação da Bacia do Alto Paraguai. Monitoramento da fauna sob impacto ambiental. 1th Edition. Uniderp, Campo Grande, pp. 119–173.

    Strüssmann, C., Ribeiro, R.A.K. Ferreira, V.L. & Béda, A. F. (2007) Herpetofauna do Pantanal Brasileiro. In: Nascimento, L.B. & Oliveira, M.E (Eds.), Herpetologia no Brasil II. Sociedade Brasileira de Herpetologia, Belo Horizonte, pp. 66–84.

    Strüssmann, C., Prado, C.P.A., Ferreira, V.L. & Ribeiro, R.A.K. (2010) Diversity, ecology, management and conservation of amphibians and reptiles in the Brazilian Pantanal: A review. In: Junk, W.J., da Silva, C.J., Cunha, C.N. & Wantzen, K.M. (Eds.), The Pantanal: Ecology, biodiversity and sustainable management of a large seasonal wetland. Pensoft, Moscow, pp. 495–519.

    Swofford, D.L. (2003) PAUP*. Phylogenetic analysis Using Parsimony (*and other methods). Version 4. Sinauer Associates, Sunderland, Massachusetts. [program]

    Townsend, T.M., Alegre, R.E., Kelley, S.T., Wiens, J.J. & Reeder, T.W. (2008) Rapid development of multiple nuclear loci for phylogenetic analysis using genomic resources: an example from squamate reptiles. Molecular Phylogenetic Evolution, 47, 129–142.

    https://doi.org/10.1016/j.ympev.2008.01.008

    Uetz, P., Freed, P. & Hošek, J. (2018) The Reptile Database. Available from: http://www.reptile-database.org (accessed 30 august 2018)

    Uzzell, T. (1973) A revision of lizards of the genus Prionodactylus, with a new genus for P. leucostictus and notes on the genus Euspondylus (Sauria, Teiidae). Postilla, 159, 1–67.

    https://doi.org/10.5962/bhl.part.11535

    Vidal, N., Kindl, S.G., Wonge, A. & Hedges, S.B. (2000) Phylogenetic relationships of xenodontine snakes inferred from 12s and 16s ribosomal RNA sequences. Molecular Phylogenetics and Evolution, 14 (3), 389–402.

    https://doi.org/10.1006/mpev.1999.0717

    Vidal, N., Dewynter, M. & Gower, D.J. (2010) Dissecting the major American snake radiation: a molecular phylogeny of the Dipsadidae Bonaparte (Serpentes, Caenophidia). Comptes Rendus Biologies, 333 (1), 48–55.

    https://doi.org/10.1016/j.crvi.2009.11.003

    Wagler, J.G. (1828) Descriptiones et icons amphibiorum. Stuttgartiae et Tubingae, Monachii, XXXVI tabs.

    https://doi.org/10.5962/bhl.title.101419

    Wagler, J.G. (1830) Natürliches System der Amphibien, mit vorangehender Classification der Saugthiere und Vogel. Ein Beitrag zur vergleichenden Zoologie. J.G. Cotta schen Buchhandlung. Munchen, Stuttgart und Tubingen, pp.

    https://doi.org/10.5962/bhl.title.58730

    Wallach, V., Williams, K.L. & Boundy, J. (2014) Snakes of the World: A Catalogue of Living and Extinct Species. CRC Press/Taylor and Francis, Boca Ratton, 1209 pp.

    https://doi.org/10.1201/b16901

    Wied, M. (1825) Beiträge zur Naturgeschichte von Brasilien. Vol. 1. Gr. H. S. priv. Landes-Industr-Comptoirs, Weimar, 91 pls.

    Zaher, H. (1999) Hemipenial morphology of the South American xenodontine snakes, with a proposal for a monophyletic Xenodontinae and a reappraisal of colubroid hemipenes. Bulletin of the American Museum of Natural History, 240, 1–168.

    Zaher, H., Grazziotin, F.G., Cadle, J.E., Murphy, R.W., Moura-Leite, J.C. & Bonatto, S.L. (2009) Molecular phylogeny of advanced snakes (Serpentes, Caenophidia) with emphasis on South American Xenodontines: a revised classification and descriptions of new taxa. Papéis Avulsos de Zoologia, 49, 115–153.

    https://doi.org/10.1590/S0031-10492009001100001