title: Allozyme relationships in hypostomines (Teleostei: Loricariidae) from the Itaipu Reservoir, Upper Rio Paraná basin, Brazil.
abstract: In an allozyme electrophoresis survey of 15 hypostomine species from the Itaipu Hydroelectric Reservoir, 25 loci from 14 enzyme systems were scored. Allozyme data allowed recording diagnostic genetic markers for all species analyzed and for some species groups within Hypostomus, a taxon which is taxonomically still unresolved in the Upper Rio Paraná basin. The mean expected heterozygosity of the species was considerably variable and hypotheses to tentatively explain this variation are discussed. A cladogram based upon the allelic frequencies of the species analyzed was produced by the continuous maximum likelihood method: Rhinelepis aspera and M. parananus were separated from the species of Hypostominae by a long branch length. Pterygoplichthys anisitsi was the sister of all the representatives of the genus Hypostomus. Within Hypostomus, two main clades were produced: in the first, H. cochliodon was the sister of the species comprising the H. plecostomus group, and in the second, the tree showed the following relationships: (H. albopunctatus (H. regani + Hypostomus sp. 3) + (H. margaritifer (H. microstomus (Hypostomus sp. 1 (H. ternetzi + Hypostomus sp. 2)). Hypostomus ternetzi and Hypostomus sp. 2 are referred to here as representatives of the H. ternetzi group.
authors.affiliation: Universidade Estadual do Centro-Oeste, CEDETEG, Departamento de Ciências Biológicas, R. Simeão Camargo Varela de Sá, 03, 85040-080 Guarapuava-PR, Brasil. chzawadzki@nupelia.uem.br
authors.forename: Cláudio Henrique
authors.initials: CH
authors.lastname: Zawadzki
authors.forename: Erasmo
authors.initials: E
authors.lastname: Renesto
authors.forename: Roberto Esser
authors.initials: RE
authors.lastname: dos Reis
authors.forename: Maurício Osvaldo
authors.initials: MO
authors.lastname: Moura
authors.forename: Rogério Pincela
authors.initials: RP
authors.lastname: Mateus
mesh_terms: D000818:Animals; D001938:Brazil; D002397:Catfishes / Q000145:classification / Q000235:genetics*; D004586:Electrophoresis; D014644:Genetic Variation; D006579:Heterozygote; D007527:Isoenzymes / Q000235:genetics*; D010802:Phylogeny; D013045:Species Specificity
chemical_list: D007527:Isoenzymes