Banca de DEFESA: MELQUIADES DE OLIVEIRA COSTA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : MELQUIADES DE OLIVEIRA COSTA
DATE: 20/12/2023
TIME: 09:00
LOCAL: Sala 432 - BMT2
TITLE:

Cytogenetic study in trahiras (Hoplias spp.) from Trombetas river basin.

KEY WORDS:

Amazon basin, Trombetas river, Ichthyofauna, Trahiras, Taxonomy, Karyotype

PAGES: 40
BIG AREA: Outra
AREA: Ciências Ambientais
SUMMARY:

The Amazon basin is the largest hydrographic province in South America and is home to more than 2,700 species of freshwater fish, however the exact number of fish species in the Amazon basin is still unknown. In recent decades, advances in knowledge of Amazonian ichthyofauna have been driven by integrative taxonomy analyses, including cytogenetic analyzes important in species classification. Trahiras (family Erythrinidae, gen. Hoplias) represent a controversial taxon that harbors a complex of cryptic species. Cytogenetic studies pointed out different evolutionary units hidden in the taxon H. malabaricus. This proposal will contribute to the advancement of knowledge about Amazonian aquatic biodiversity and aims to investigate the karyotypic pattern of trahiras collected in the Trombetas river basin. The fish were collected between the months of November/2022 and November/2023. To characterize the karyotypic macrostructure, conventional staining, C-banding and Ag-NOR staining methods were adopted. Three distinct karyotypic patterns were observed in relation to the diploid number (2n), characterized as 2n=40, 2n=42 and 2n=50 chromosomes. C banding revealed greater accumulation of constitutive heterochromatin in the 2n=40 karyotype, with typical location in the centromeric region. The number and position of the nucleolar organizing regions varied from 2 sites in the karyotype with 2n=50, to 4 sites in the karyotype with 2n=40 and 8 sites in the karyotype with 2n=42. The results obtained show a new karyotypic variant in the Hoplias curupira species, which reinforces the importance of conservation units in maintaining biodiversity and reinforces the need for future studies in these areas.

COMMITTEE MEMBERS:
Presidente - 1327077 - LUIS REGINALDO RIBEIRO RODRIGUES
Interno - 1796322 - RICARDO SCOLES CANO
Externo ao Programa - 3304333 - RENATO DA SILVA BANDEIRA - UFOPAExterno à Instituição - ADILIA DOS PRAZERES DA ROCHA NOGUEIRA - UFOPA