Banca de QUALIFICAÇÃO: JOEDMA GRACIENE DA SILVA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : JOEDMA GRACIENE DA SILVA
DATE: 16/02/2026
TIME: 08:30
LOCAL: Remota
TITLE:

Phylogeography and species boundaries of Physalaemus Fitzinger, 1826 (Amphibia, Anura, Leptodactylidae) associated with the Caatinga domain, northeastern Brazil: an integrative taxonomic approach  

KEY WORDS:

cryptic species; integrative taxonomy; mitochondrial DNA barcode; Neotropical amphibians; phylogeography

PAGES: 112
BIG AREA: Ciências Biológicas
AREA: Zoologia
SUBÁREA: Taxonomia dos Grupos Recentes
SUMMARY:

The Caatinga is one of the main biomes of the South American Diagonal of Open Formations and is characterized by high environmental heterogeneity, which is reflected in complex patterns of biological diversification. Despite this, amphibian diversity in this biome remains underestimated, particularly in groups exhibiting strong morphological conservatism. The genus Physalaemus (Leptodactylidae), especially the Physalaemus cuvieri species group, represents an appropriate model for investigating processes of species delimitation and geographic structuring in seasonal environments, as it comprises widely distributed, morphologically similar species with previous evidence of hidden genetic diversity. In this study, we investigated species boundaries and patterns of geographic structuring of the P. cuvieri group associated with the Caatinga in northeastern Brazil, using an integrative approach based on an extensive mitochondrial barcode (16S gene) combined with bioacoustic data. We analyzed 995 DNA sequences, including newly generated data and sequences retrieved from GenBank, covering a large portion of the group’s distribution in South America, with emphasis on the Caatinga. Genealogical relationships were inferred using Bayesian Inference and Maximum Likelihood analyses. Species delimitation was assessed using the ABGD, GMYC, and PTP methods. Our results revealed strong genetic structuring within the group, with the identification of multiple evolutionary lineages in the Caatinga. In total, we recovered eight lineages within the P. cuvieri species group in the biome, four of which represent potential undescribed species. Species traditionally treated as widely distributed, such as P. cicada and P. albifrons, were shown to comprise deeply divergent and geographically structured lineages. The observed patterns suggest that the environmental heterogeneity of the Caatinga, together with historical factors such as Pleistocene climatic fluctuations and regional variation in precipitation regimes, may have played a central role in the diversification of the group, whereas major rivers, such as the São Francisco River, acted variably across taxa. Overall, we demonstrate that the diversity of the Physalaemus cuvieri group in the Caatinga has been significantly underestimated by traditional taxonomic approaches, reinforcing the need for integrative frameworks for species delimitation and for understanding the evolutionary processes shaping the herpetofauna of the Brazilian semi-arid region.   

COMMITTEE MEMBERS:
Externo à Instituição - IURI RIBEIRO DIAS - UESC
Presidente - 1678338 - ADRIAN ANTONIO GARDA
Externo ao Programa - 039.253.981-04 - LEANDRO ALVES DA SILVA