title: Mitochondrial D-loop nucleotide diversity in Astyanax (Osteichthyes, Characidae) from the upper Paraná and upper Paraguay River basins.
abstract: The morphological discrimination between the species Astyanax  altiparanae and A. asuncionensis of the upper Paraná River and  Paraguay River basins, respectively, has always been difficult. Two D-loop  haplogroups of A. altiparanae are known, one with the presence (AltoPR)  or the absence (AltoPR-D) of a 32-bp block similar to that in A.  asuncionensis. We examined these samples to characterize A. altiparanae and  verify whether A. asuncionensis occurred in the upper Paraná River prior  to the submergence of the Sete Quedas Falls when Itaipu reservoir was  impounded. D-loop sequences were analyzed in A. altiparanae of the upper  Paraná and Iguaçu Rivers and those of A. asuncionensis of the upper  Paraguay River. The haplogroup AltoPR was found at all sites of the upper  Paraná and Iguaçu Rivers, whereas AltoPR-D occurred in the Itaipu reservoir,  floodplain and in the Tietê and Grande Rivers. Two haplogroups of A.  asuncionensis were identified and both did not have the 32-bp block.  However, AltoPR and AltoPR-D differed from one another in 5.1% of their bases  and between 8.9 and 12.5% with regard to the haplogroups of the upper Paraguay  basin. Further, AltoPR-D occurred in the Grande River upstream the Marimbondo  Falls and other older reservoirs than Itaipu. The results reject the hypothesis  of the establishment of A. asuncionensis and suggest that the haplogroup  AltoPR-D existed in the upper Paraná River before the impounding of the Itaipu  reservoir. Moreover, morphological similarity and high genetic variation within  the altiparanae/asuncionensis group suggest the existence of a  cryptic species complex.
authors.affiliation: Departamento de Biologia Celular e Genética, Universidade Estadual de Maringá, Maringá, PR, Brasil. ajprioli@nupelia.uem.br
authors.forename: A J
authors.initials: AJ
authors.lastname: Prioli
authors.forename: V A
authors.initials: VA
authors.lastname: Carlo
authors.forename: T V
authors.initials: TV
authors.lastname: Soria
authors.forename: S M A P
authors.initials: SM
authors.lastname: Prioli
authors.forename: C S
authors.initials: CS
authors.lastname: Pavanelli
authors.forename: R A
authors.initials: RA
authors.lastname: Prioli
authors.forename: V N
authors.initials: VN
authors.lastname: Gomes
authors.forename: H F
authors.initials: HF
authors.lastname: Júlio
authors.forename: L M
authors.initials: LM
authors.lastname: Prioli
mesh_terms: D000818:Animals; D001483:Base Sequence; D001938:Brazil; D060126:Characidae / Q000235:genetics*; D017931:DNA Primers; D004272:DNA, Mitochondrial / Q000235:genetics*; D019143:Evolution, Molecular; D006239:Haplotypes; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic; D012689:Sequence Homology, Nucleic Acid
chemical_list: D017931:DNA Primers; D004272:DNA, Mitochondrial