Diversidade e estrutura genética em populações de vida livre do mico-leão preto (Leontopithecus chrysopygus): implicações para a conservação

Abstract

Understanding the genetic diversity and population structure of endangered species provides essential information for the development of conservation actions. The black lion tamarin (Leontopithecus chrysopygus), an endemic primate from the Atlantic Forest of São Paulo state, is currently classified as endangered and subject to conservation actions aiming to assure its survival within a biome historically threatened by deforestation and fragmentation. Low density, isolated populations pose risks to the genetic variability and population viability of the species. Moreover, knowledge gaps regarding the genetics of free-ranging populations can compromise the design of effective management and conservation strategies. Wild populations of the black lion tamarin from ten different locations across the species’ range in the Upper, Middle and Lower Paranapanema River regions were investigated, focusing on currently undersampled areas. Fragments of the D-loop region of mitochondrial DNA and microsatellite loci were analyzed in order to investigate the genetic diversity and population structure, assess population viability in terms of retention of genetic diversity, and infer kinship relationships and socio-reproductive aspects. Results revealed low levels of genetic diversity in 70% of the analyzed populations, with only three populations showing moderate diversity levels. Evidence of population bottlenecks was identified in all populations, and only the Morro do Diabo population consistently showed long-term genetic viability. Mating systems showed flexibility, with evidence of polygamy in 25% of social groups, including cases of polygyny and polyandry. Genetic structure patterns were detected for both markers, which were interpreted considering historical and contemporary factors that possibly shaped the distribution of genetic variability in the different regions of the species’ current range. Results presented here contribute to the understanding of the diversity and genetic structure of the black lion tamarin and provide relevant information for planning management and conservation actions aimed at maintaining the viability of the species in the wild.