Genetic diversity in ex situ populations of the endangered Leontopithecus chrysomelas and implications for its conservation.

Leontopithecus chrysomelas, the Golden-headed Lion Tamarin (GHLT), is an endangered and endemic Neotropical primate from the Atlantic Forest of Brazil that has suffered a reduction of its habitat and population size in the wild. Ex situ populations have been established as a relevant alternative to safeguard the species and retain its genetic diversity and evolutionary potential. This study evaluated the genetic diversity and structure of the two main Brazilian captive populations of GHLT, which have been under human care at the Primatology Center of Rio de Janeiro (CPRJ) and the Zoological Park Foundation of São Paulo (FPZSP). Our results revealed levels of genetic diversity overall comparable to those observed for other Leontopithecus species and for ex situ and in situ populations of GHLT previously studied. Bayesian and principal coordinate analyses showed a moderate differentiation between CPRJ and FPZSP populations. Both populations presented observed heterozygosity values higher than expected heterozygosity values for most of the microsatellites used in this study, suggesting that the management has been efficient in avoiding an increase in homozygosity. However, simulations point to a significant loss of genetic diversity in the next 100 years, mainly in the FPZSP population. Such data are relevant for further decision-making on the metapopulation management of L. chrysomelas in captive conditions and for integrating in situ and ex situ conservation plans.

Next-Generation Sequencing of the Complete Mitochondrial Genome of the Endangered Species Black Lion Tamarin Leontopithecus chrysopygus (Primates) and Mitogenomic Phylogeny Focusing on the Callitrichidae Family.

We describe the complete mitochondrial genome sequence of the Black Lion Tamarin, an endangered primate species endemic to the Atlantic Rainforest of Brazil. We assembled the Leontopithecus chrysopygus mitogenome, through analysis of 523M base pairs (bp) of short reads produced by next-generation sequencing (NGS) on the Illumina Platform, and investigated the presence of nuclear mitochondrial pseudogenes and heteroplasmic sites. Additionally, we conducted phylogenetic analyses using all complete mitogenomes available for primates until June 2017. The single circular mitogenome of BLT showed organization and arrangement that are typical for other vertebrate species, with a total of 16618 bp, containing 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 1 non-coding region (D-loop region). Our full phylogenetic tree is based on the most comprehensive mitogenomic dataset for Callitrichidae species to date, adding new data for the Leontopithecus genus, and discussing previous studies performed on primates. Moreover, the mitochondrial genome reported here consists of a robust mitogenome with 3000X coverage, which certainly will be useful for further phylogenetic and evolutionary analyses of Callitrichidae and higher taxa.