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The capybara, Hydrochoerus hydrochaeris, is a semiaquatic herbivorous rodent widely distributed in South American wetlands. Some authors have proposed the existence of two species, several subspecies, and different Evolutionarily Significant Units (ESUs) in the Hydrochoerus genus. However, the available genetic studies of capybaras are limited in their geographical scope. Thus, we examined genetic variation in 387 sequences of the mitochondrial control region (124 generated by the authors and 263 obtained from GenBank) and performed phylogeographic analyses to determine patterns of geographic variation in capybaras sampled in seven South American countries, representing a large portion of the distribution range of the species. Based on these analyses, four ESUs were identified. In addition, within one of these units, two distant geographic populations were identified in the Trans-Andean Colombia (putative H. isthmius population) and the cis-Andean area of the Napo River in Peru and Ecuador. This result and the genetic distances between these ESUs agree with the idea of a unique capybara species. Mismatch distributions and Bayesian skyline plots suggested that capybaras have undergone processes of population decline associated with the adverse weather conditions of the late Pleistocene, followed by population expansions associated with the climatic conditions of the Holocene Climatic Optimum. Phylogenetic trees support the previous hypothesis that the species originated in Western Amazon. However, as our results are based on a single mitochondrial fragment, these results are not conclusive. New studies, including samples from other sites and more mitochondrial and nuclear markers, may elucidate the evolutionarily history of capybaras. [ABSTRACT FROM AUTHOR]

The systematics of the Humboldt's wooly monkeys (L. lagothricha; Atelidae) is essential to preserve this Neotropical primate species. Traditionally, four morphological subspecies have been described, which recently have been molecularly confirmed. However, no population genetics studies have been carried out throughout the geographical distribution of one of these subspecies, Lagothrix lagothricha poeppigii. For this reason, we analyzed nine mitochondrial genes of L. l. poeppigii mainly collected from the Ecuadorian and Peruvian Amazon in order to better understand the evolutionary history of this taxon. The mitochondrial genetic diversity levels (haplotype and nucleotide diversity) we estimated are likely the highest yet reported for L. lagothricha. Our results did not detect important genetic structure within L. l. poeppigii. Furthermore, our phylogenetic analyses did not detect any relevant molecular cluster in the area where Groves hypothesized the existence of L. poeppigii castelnaui. Therefore, based on these data, castelnaui is not a valid taxon from a molecular perspective. The most differentiated subpopulation within L. l. poeppigii was from Morona-Santiago province (Ecuador) and had a genetic distance of 0.8–1.2% relative to the other subpopulations studied. However, this genetic distance range is within the variability found within a population. We estimated the mitochondrial temporal diversification within L. l. poeppigii to have occurred during the Pleistocene, 1.8–1.2 million years ago. Similarly, all our analyses detected a strong Pleistocene female population expansion for this taxon. Diverse spatial genetic analyses, perhaps with the exception of Monmonier's Algorithm, did not detect differentiated taxa within the area analyzed for L. l. poeppigii. These genetics results could be of importance to conservation efforts to preserve this taxon as one unit. [ABSTRACT FROM AUTHOR]

Knowledge of how a species is divided into different genetic units, and the structure among these units, is fundamental to the protection of biodiversity. Procyonidae was one of the families in the Order Carnivora with more success in the colonization of South America. The most divergent species in this family is the kinkajou (Potos flavus). However, knowledge of the genetics and evolution of this species is scarce. We analyzed five mitochondrial genes within 129 individuals of P. flavus from seven Neotropical countries (Mexico, Guatemala, Honduras, Colombia, Ecuador, Peru, and Bolivia). We detected eight different populations or haplogroups, although only three had highly significant bootstrap values (southern Mexico and Central America; northern Peruvian, Ecuadorian, and Colombian Amazon; and north-central Andes and the southern Amazon in Peru). Some analyses showed that the ancestor of the southern Mexico–Central America haplogroup was the first to appear. The youngest haplogroups were those at the most southern area analyzed in Peru and Bolivia. A "borrowed molecular clock" estimated the initial diversification to have occurred around 9.6 million years ago (MYA). All the spatial genetic analyses detected a very strong spatial structure with significant genetic patches (average diameter around 400–500 km) and a clinal isolation by distance among them. The overall sample and all of the haplogroups we detected had elevated levels of genetic diversity, which strongly indicates their long existence. A Bayesian Skyline Plot detected, for the overall sample and for the three most significant haplogroups, a decrease in the number of females within the last 30,000–50,000 years, with a strong decrease in the last 10,000–20,000 years. Our data supported an alignment of some but not all haplogroups with putative morphological subspecies. We have not discounted the possibility of a cryptic kinkajou species. [ABSTRACT FROM AUTHOR]

We sequenced mitochondrial COI and COII genes (1,377 base pairs) of 166 woolly monkeys (Lagothrix) to determine the phylogenetic relationships of tschudii in reference to the other taxa within the genus Lagothrix, to provide the first genetic diversity level estimates for tschudii, and to reconstruct the historical demographic evolution of this taxon. The sample set included, for the first time, 10 individuals of the elusive tschudii taxon sensu Groves from southern Peru and northern Bolivia. Our phylogenetic analyses showed that these 10 exemplars formed a statistically significant and differentiated (molecularly and morphologically) monophyletic clade relative to other traditional subspecies of Lagothrix lagothricha. Therefore, tschudii should be recognized as a fifth subspecies: Lagothrix lagothricha tschudii. The temporal divergence of the ancestors of tschudii and L. l. cana was estimated to have occurred around 1.8 million years ago (MYA). Additionally, mitochondrial diversification within tschudii started no later than 0.96 MYA (Bayesian Inference) or 0.88 MYA (Median Joining -Network), respectively. In contrast to the phylogenetic trees, the FSTstatistic and the gene flow estimates showed L. l. lugens to be the least differentiated taxon of L. lagothricha from L. l. tschudii. Based on genetic distances, L. l. tschudii had the smallest average genetic distance from the other subspecies of L. lagothricha.It was also the taxon within L. lagothricha that had the smallest genetic distance from L. flavicauda. It should be related to L. l. tschudii as the first original taxon in L. lagothricha. Furthermore, the Andean mountains were extremely important in the original diversification of the Lagothrix genus and in the original diversification of L. lagothricha. Although L. l. tschudii has the smallest geographical range of all the taxa of L. lagothricha, its genetic diversity is even higher than in other taxa with wider geographical ranges, such as L. l. lagothricha and L. l. cana. L. l. tschudii showed a very slight demographic increase during the Pleistocene with a decrease of females in the last 10,000 Y, similar to that found for L. l. lugens in a previous study., (© 2019 S. Karger AG, Basel.)