Genetic differentiation in the populations of red piranha, Pygocentrus nattereri Kner (1860) (Characiformes: Serrasalminae), from the river basins of northeastern Brazil

Abstract

The red piranha, Pygocentrus nattereri, is an important resource for artisanal and commercial fisheries. The present study determines the genetic differentiation among P. nattereri populations from the northeastern Brazilian state of Maranhão. The DNA was isolated using a standard phenol-chloroform protocol and the Control Region was amplified by PCR. The PCR products were sequenced using the didesoxyterminal method. A sequence of 1039 bps was obtained from the Control Region of 60 specimens, which presented 33 polymorphic sites, 41 haplotypes, һ =0.978 and π =0.009. The neutrality tests (D and Fs) were significant (P < 0.05) for most of the populations analyzed. The AMOVA indicated that most of the molecular variation (72%) arises between groups. The fixation index was highly significant (F ST = 0.707, P < 0.00001). The phylogenetic analyses indicated that the specimens represented a monophyletic group. Genetic distances between populations varied from 0.8% to 1.9%, and were <0.5% within populations. The degree of genetic differentiation found among the stocks of P. nattereri indicates the need for the development of independent management plans for the different river basins in order to preserve the genetic variability of their populations. Keywords

Molecular characterization and genetic relationships of seven piranha species of the genera Serrasalmus and Pygocentrus (Characiformes: Serrasalmidae) from Paraná-Paraguay, São Francisco and Tocantins River basins in Brazil

“…Although the value of p-distance detected between the species were low (2.48%), this is an expected result, since the speciation event leading to P. nattereri and P. piraya occurred recently, during the last 2.6 ± 0.2 Ma (Mateussi et al, 2019). We also detected high genetic variability within P. nattereri, as previously reported by Mateussi et al (2019) and Luz et al (2015). Specimens of P. nattereri were separate in the dendrograms according to the sample locality.…”

Molecular Data Reveal Multiple Lineages in Piranhas of the Genus Pygocentrus (Teleostei, Characiformes)

“…For example, the phylogeographic study of Pygocentrus based on the mtDNA control region found P. nattereri with structured genetic lineages in which the Paraná, Ucayali and Madeira lineages appeared genetically closer to each other than to the lineage from mainstream Rio Amazonas [13]. Population genetic studies within P. nattereri from the northeastern Brazil [16] and from the Rio Solimões/Amazonas [17] have also shown high levels of genetic diversity and significant genetic differentiation among populations. The maintenance of P. nattereri in captivity likely enabled the introduction of P. nattereri in several Asian rivers including in Bangladesh [18], China [9] and the Philippines [19,20].…”

“…Here, we used partial sequences of the mitochondrial gene cytochrome c oxidase subunit I ( COI ) and modern phylogenetic and species delimitation methods in order to (1) test the morphological hypothesis of the presence of three species of Pygocentrus [10], (2) test the population genetic hypothesis of multiple genetically-structured populations of P. nattereri [13,16,17], and (3) determine the geographic origin of recently introduced specimens of P. nattereri in Asia [20].…”