Identificação citogenética e molecular de cariomorfos de Hoplias malabaricus (Characiformes, Erythrinidae) na bacia do baixo rio Iguaçu

Abstract

Hoplias malabaricus is a complex group in the Erythrinidae family. In the H. malabaricus group there are seven described species. One of these species is H. malabaricus, which is a species complex with seven described karyomorphs. For the Iguaçu watershed, studies related to the distribution of karyomorphs are still scarce and most studies focus on the Upper Iguaçu, while for the middle and lower Iguaçu studies are scarce. Furthermore, the lower Iguaçu suffers anthropic influences, mainly with the introduction of exotic species and the construction of hydroelectric dams due to the high number of waterfalls. Both influences can lead to the extinction of several species. Considering the low number of studies related to karyomorphs of H. malabaricus, and the various issues relevant to this group, the present study aimed to analyze individuals of this species in an integrative way through cytogenetic techniques and barcode DNA. As many sequences as possible from the H. malabaricus group from the Bold System were used in our analyses. Our results showed the presence of three karyotype in sympatry. Two cytotypes of karyomorph A (A1 and A2) and the karyomorph D. Our hypothesis is: 1. Cytotype A1 is the chromosomal form native to the Iguaçu River Basin; 2. Cytotype A2 may represent Hoplias argentinensis specie; 3. Karyomorph D may represent the specie Hoplias misionera; 4. Cytotype A2 and karyomorph D may have been introduced in the Lower Iguaçu River. Our results allowed to increase data regarding the distribution of karyomorphs and species of the H. malabaricus group. In addition to showing that the integration of cytogenetic tools and barcode DNA can be very efficient for the H. malabaricus group.