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Issue: Vol. 933 No. 1: 8 Apr. 2005
Type: Articles
Published: 2005-04-08
DOI: 10.11646/zootaxa.933.1.1
Page range: 1–14
Abstract views: 78
PDF downloaded: 3

A new Gymnotus (Teleostei: Gymnotiformes: Gymnotidae) from the Pantanal Matogrossense of Brazil and adjacent drainages: continued documentation of a cryptic fauna

Museu de Zoologia, Universidade de São Paulo, São Paulo, 042563-000, Brazil
Department of Biology, University of Louisiana, Lafayette, LA, 70504-2451
Departamento de Biologia, Instituto de BiociÍncias, Universidade de S„o Paulo, 05508-900, Brazil
Departamento de Biologia, Instituto de BiociÍncias, Universidade de S„o Paulo, 05508-900, Brazil
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Departamento de Biologia, Instituto de BiociÍncias, Universidade de S„o Paulo, 05508-900, Brazil
Pisces Gymnotiformes microsatellite chromosome cryptic diversity

Abstract

Here we describe a new species of Gymnotus, G. pantanal n. sp., from the Pantanal Matogrossense of Brazil, using morphological, cytogenetic, and molecular data. Specimens ascribed to the new species are also known from areas downstream in Paraguay, and from the adjacent Guaporé basin of Bolivia. The new species most closely resembles G. anguillaris in possessing an elongate body, slender profile, long body cavity, and shorter head than other congeners. The new species also resembles G. anguillaris in the presence of pale narrow bands restricted to the area below the lateral line on the anterior half of the body. The new taxon differs from G. anguillaris in possessing more narrowly set eyes, a wider and deeper head, a larger branchial opening, longer pectoral fins with more fin rays, and fewer pored posterior lateral-line scales. The new species inhabits rooted grasses and floating macrophytes in small creeks and along the banks of larger blackwater rivers. Populations are found syntoptically with G. inaequilabiatus and G. sylvius. Compared with these species, the new species exhibits a distinct combination of microsatellite DNA amplification patterns, and chromosomal and external features. These results confirm earlier studies showing the power of a multidisciplinary approach to characterizing the enormous and often cryptic diversity of Neotropical fishes.

References

  1. Albert, J.S. (2001) Species diversity and phylogenetic systematics of American knifefishes (Gymnotiformes, Teleostei). Miscellaneous Publications of the Museum of Zoology, University of Michigan. 190, 1–127.

    Albert, J.S. & Crampton W.G.R. (2001) Five new species of Gymnotus (Teleostei: Gymnotiformes) from an Upper Amazonian floodplain, with descriptions of electric organ discharges and ecology. Ichthyological Exploration of Freshwaters, 12(3), 241–226.

    Albert, J.S. & Crampton, W.G.R. (2003) Seven new species of the Neotropical electric fish Gymnotus (Teleostei, Gymnotiformes) with a redescription of G. carapo (Linnaeus). Zootaxa, 287: 1–54.

    Albert, J.S. & Fink, W.L. (1996) Sternopygus xingu, a new species of electric fish from Brazil (Teleostei: Gymnotoidei), with comments on the phylogenetic position of Sternopygus. Copeia 1996, 85–102.

    Albert, J.S. & Miller, R.R. (1995) Gymnotus maculosus, a new species of electric fish from Middle America (Teleostei: Gymnotoidei), with a key to the species of Gymnotus. Proceedings of Biological Society of Washington, 108(4), 662–678.

    Albert, J.S., Fernandes-Matioli, F.M. C. & Almeida-Toledo, L.F. (1999) A new species of Gymnotus (Gymnotiformes, Teleostei) from Southeastern Brazil: towards the deconstruction of Gymnotus carapo. Copeia 1999(2), 410–421.

    .Albert, J.S., Crampton, W.G.R., Thorsen, D. H. & Lovejoy, N.R. (2005) Phylogenetic systematics and historical biogeography of the Neotropical electric fish Gymnotus (Teleostei: Gymnotiformes). Systematic and Biodiversity, 2(4), 375–417.

    Crampton, W.G.R. (1998) Effects of anoxia on the distribution, respiratory strategies and electric signal diversity of gymnotiform fishes. Journal of Fish Biology, 53, 307–330.

    Crampton W.G.R., Lovejoy, N.R. & Albert, J.S. (2003) Gymnotus ucamara: a new species of Neotropical electric fish from the Peruvian Amazon (Ostariophysi: Gymnotidae), with notes on ecology and electric organ discharges. Zootaxa, 277, 1–18.

    Crampton, W.G.R., Thorsen, D.H. & Albert. J.S. (2005) Three new species from a diverse sympatric assemblage of Gymnotus (Gymnotiformes: Gymnotidae) in the lowland Amazon basin, with notes on ecology. Copeia, (1), 82–99.

    Ellis, M.M. (1913). The gymnotid eels of tropical America. Memoires Carnegie Museum, 6, 109–195.

    Fernandes-Matioli, F.M.C., Marchetto, M.C.N., Almeida-Toledo, L.F. & Toledo-Filho, S.A. (1998) High intraspecific karyologycal conservation in four species of Gymnotus (Pisces: Gymnotiformes) from Southeastern Brazilian basins. Caryologia, 51, 221–234.

    Fernandes-Matioli, F.M.C., Matioli, S.R & Almeida-Toledo, L.F. (2000) Species diversity and geographic distribution of Gymnotus (Pisces: Gymnotiformes) through analysis of nuclear (GGAC)n microsatellites. Genetics and Molecular Biology, 23, 803–807.

    Fink, S.V. & Fink, W. L. (1981) Interrelationships of the ostariophysan fishes (Teleostei). Zoological Journal of the Linnean Society, London, 72, 297–353.

    Foresti, F., Almeida-Toledo, L.F. & Toledo-Filho, S.A. (1981) Polymorphic nature of nucleolus organizer regions in fishes. Cytogenetics and Cell Genetics, 31, 137–144.

    Hoedeman, J. J. (1962) Notes on the ichthyology of Surinam and other Guianas. 9. New records of gymnotid fishes. Bulletin of Aquatic Biology, 53–60.

    Howell, W. M. & Black, D. A. (1980) Controlled silver-staining of nucleolus organizer regions with a protective colloidal developer: I — step method. Experientia, 36, 1014–1015.

    Hrbeck, T. & Larson, A. (1999). The evolution of diapause in the killifish family Rivulidae (Atherinomorpha, Cyprinodontiformes): A molecular phylogenetic and biogeographic perspective, Evolution 53, 1200–1216.

    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 1985, 802–832.

    Mago-Leccia, F. (1994) Electric fishes of the continental waters of America. Biblioteca de la Academia de Ciencias Fisicas, Matematicas, y Naturales. Caracas, Venezuela, 29, 1–206.

    Murphy, W.J. & Thomerson, J.E. (1999) Phylogeny of the Neotropical killifish family Rivulidae (Cyprinodontiformes, Aplocheiloidei) inferred from mitochondrial DNA sequences, Molecular Phylogeny and Evolution, 13, 289–301.

    Nelson, J.S. (1994) Fishes of the World. 3 ed., John Wiley and Sons, Inc. U.S.A., 600 pp.

    Sambrook, J., Fritsch, E.F. & Maniats T. (eds.). (1989) Molecular cloning, a laboratory Manual. 2nd ed., Cold Spring Harbor Laboratory, Cold Spring Harbor, NY.

    Taylor, W.R. & Van Dyke, G.C. (1985). Revised procedures for staining and clearing small fishes and other vertebrates for bone and cartilage study. Cybium, 9, 107–119.

    Weitzman, S.H. (1962). The osteology of Brycon meeki, a generalized characid fish, with an osteological definition of the family. Stanford Ichthyological Bulletin, 8, 1–77.