Abstract：
Astyanax is one of the most specious fish groups in the Neotropical region, with many cryptic species, which represents a challenge for correct identification through traditional taxonomic methods. Psalidodon is a recently resurrected genus group of species previously belonging to Astyanax, specifically those with extensive chromosomal variation of the A. scabripinnis and fasciatus complexes. In the present study, the mitochondrial genes cytochrome c oxidase subunit 1 (COI), mitochondrial ATP synthase 6 and 8 (ATPase 6/8), and NADH dehydrogenase subunit 2 (ND2) were used in conjunction with chromosomal data to characterize molecularly and cytogenetically populations of Astyanax and Psalidodon from rivers and streams of the Ivaí River Basin (Paraná Basin). The results demonstrated the effectiveness of the integrative use of molecular and cytogenetic techniques, with the confirmation of at least three species for the sampled sites: A. lacustris, P. paranae, and P. fasciatus, which showed inter- and intrapopulation karyotype variations. In addition, extensive haplotypic variation can be observed for these species within the Ivaí River Basin and throughout the Paraná River Basin. The data demonstrate a hidden diversity among the species analyzed, enrich the ichthyofaunistic knowledge of small rivers and streams, and contribute to future conservation projects in these areas.
摘要：
Astyanax是新热带地区最可疑的鱼群之一，有许多神秘的物种，这代表了通过传统分类学方法进行正确识别的挑战。Psalidodon是最近复活的属，以前属于Astyanax，特别是那些具有大量染色体变异的S.a.scabripinnis和fasciatus复合体。在本研究中,线粒体基因细胞色素C氧化酶亚基1（COI），线粒体ATP合酶6和8（ATP酶6/8），和NADH脱氢酶亚基2（ND2）与染色体数据结合使用，以表征伊瓦伊盆地（巴拉那盆地）河流和溪流中的Astyanax和Psalidodon的分子和细胞遗传学种群。结果证明了分子和细胞遗传学技术的综合使用的有效性，随着采样地点至少有三种物种的确认：A.lacustris，P.paranae,和P.fasciatus,显示了种群间和种群内的核型变异。此外,在伊瓦伊流域和整个巴拉那河流域内，可以观察到这些物种的广泛单倍型变异。数据表明所分析物种之间隐藏的多样性，丰富了小河小溪的鱼类知识，并为这些地区的未来保护项目做出贡献。
