Banca de DEFESA: DENIS BRUNO SANTOS MARQUES NUNES

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : DENIS BRUNO SANTOS MARQUES NUNES
DATE: 15/02/2023
TIME: 14:00
LOCAL: Remoto através de plataforma google meet
TITLE:

DNA barcode highlights taxonomic warnings and cryptic diversity of São Francisco river basin fishes, in the Neotropical region

KEY WORDS:

Neotropical fish, COI, genetic divergence, cryptic lineages, identification errors, species complex.

PAGES: 73
BIG AREA: Ciências Biológicas
AREA: Genética
SUBÁREA: Genética Animal
SUMMARY:

The São Francisco River (SF) watershed in the neotropical region is of great socioeconomic relevance for Brazil. However, its ichthyofauna has been affected by many anthropogenic factors, culminating in several species becoming extinct locally along its stretches. This important basin is known for its diversity and endemism, with 178 species recorded, of which 60% were considered endemic. Studies on the genetic diversity of the ichthyofauna inhabitants of this basin have been carried out more punctually, involving a few species, or when comprehensive, involving a few stretches along its extension. In some of the stretches of the SF, genetic knowledge is still diffuse and incipient, mainly in the most affected regions, such as the Submiddle (practically barred) and Lower (silted). In this context, the present study aimed to fill this knowledge gap, in order to evaluate the effects of geographic scale on genetic diversity and evolutionary cohesion in fish species with different habitat preferences, and widely distributed in the SF basin. Our data evaluated 90 species and revealed distinct patterns of genetic divergence (DGs): DG<1% (73 species or 81.81%), 1%<DG<2% (9 species or 10%) and DG>2% (8 species or 8.89%). Furthermore, we detected misidentifications involving eight taxa: Phenacorhamdia tenebrosa, Cetopsorhamdia iheringi, Imparfinis mirini, I. minutus, Characidium zebra, C. lagosantense, C. fasciatum and C. gomesi. On the other hand, we found some cases of species complex and taxonomies warnings involving the genera Astyanax and Psalidodon. The cryptic and structured diversity in the evaluated species does not seem to be associated with geographic distance. Our results highlight the multiple historical processes that the São Francisco river basin experienced during its hydrogeological formation and has been facing through anthropic effects, which has heterogeneously affected the ichthyofauna of the inhabitants of this basin with different genetic signatures. In the future, we hope this information can serve as a foundation for management and conservation plans for these species in the SF basin.

 

BANKING MEMBERS:
Interno(a) - 2360032 - KIM RIBEIRO BARAO
Externo(a) à Instituição - PABLO ARIEL MARTINEZ - UFS
Interno(a) - 1714987 - TAMI MOTT
Presidente - 2265276 - UEDSON PEREIRA JACOBINA