Descrição
Made available in DSpace on 2021-06-25T12:28:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-11-01
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundacao Araucaria (Fundacao Araucaria de Apoio ao Desenvolvimento Cientifico e Tecnologico do Estado do Parana), Brazil
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
This paper presents results from a comparative analysis of cytogenetic markers, DNA barcode, molecular delimitation and population genetics among four groups of Apareiodon samples inhabiting four headwater streams feeding the Tocantins River in Brazil's Tocantins River Basin. Apareiodon is a genus of Parodontidae, a Neotropical fish family whose members show often-subtle morphological diagnostic characters that complicate identification of its constituent species. The samples were previously morphologically identified as Apareiodon machrisi, Apareiodon cavalcante, Apareiodon sp. 1, and Apareiodon sp. 2. The cytogenetic results showed a shared diploid number of 54 chromosomes, and no heteromorphic sex chromosomes were detected. In situ localization of repetitive DNA sequences (18S and 5S ribosomal DNAs, (GATA)(n) sequence, pPh2004 satellite DNA, and WAp repetitive fraction) revealed karyotype differences among the four groups of samples. The K2P genetic distance among the groups ranged from 0.79 to 4.27%. Species delimitation analyses diverge in taxa number: general mixed Yulecoalescent data suggested the occurrence of three species; and the Bayesian and neighbor-joining trees revealed four clades, three of them being supported clades (A. machrisi thorn Apareiodon sp. 1, A. cavalcante, and Apareiodon sp. 2). Haplotypes did not overlap and high Fst values were observed among the groups. The data suggest that these samples have had a recent parapatric divergence: A. cavalcante and A. machrisi are valid species; Apareiodon sp. 1 may be a lineage related to A. machrisi, possibly undergoing an incipient process of speciation; and Apareiodon sp. 2 may be a new Apareiodon molecular operational taxonomic unit. (c) 2020 Elsevier GmbH. All rights reserved.
Univ Fed Amazonas, Dept Genet, Ave Gen Rodrigo Octavio,6200, BR-69080900 Manaus, Amazonas, Brazil
Univ Fed Parana, Ctr Politecn, Programa Posgrad Genet, Jardim Amer,Caixa Postal,19071, BR-81531990 Curitiba, Parana, Brazil
Univ Fed Sao Carlos, Dept Genet & Evolucao, Rodovia Washington Luis Km 235, BR-13565905 Sao Carlos, SP, Brazil
Univ Tecnol Fed Parana, Campus Santa Helena, BR-85892000 Santa Helena, PR, Brazil
Univ Estadual Oeste Parana, Ctr Ciencias Biol & Saude, Rua Univ,2069, BR-85819110 Cascavel, PR, Brazil
Univ Estadual Paulista, Inst Biociencias, Dept Morfol, Distrito Rubiao Jr,S-N, BR-18618970 Botucatu, SP, Brazil
Univ Estadual Maringa, Nucleo Pesquisas Ictiol & Aquicultura, Ave Colombo,5790, BR-87020900 Maringa, PR, Brazil
Univ Estadual Paulista, Inst Biociencias, Dept Morfol, Distrito Rubiao Jr,S-N, BR-18618970 Botucatu, SP, Brazil
