The role of Pleistocene climate change in the genetic variability, distribution and demography of Proechimys cuvieri and P. guyannensis (Rodentia: Echimyidae) in northeastern Amazonia

Claudia Regina Silva (1, 2) , Camila Cherem Ribas (1) , Maria Nazareth F. da Silva (1) , Rafael Nascimento Leite (1) , François Catzeflis (3) , Duke S Rogers (4) , Benoit de Thoisy (5)

1 INPA - Instituto Nacional de Pesquisas da Amazônia = National Institute of Amazonian Research
2 IEPA - Instituto de Pesquisas Científicas e Tecnológicas do Estado do Amapá
3 UMR ISEM - Institut des Sciences de l'Evolution de Montpellier
4 BYU - Brigham Young University
5 Institut Pasteur de la Guyane

The spiny rats, genus Proechimys, have the highest species richness within the Echimyidae family, as well as species with high genetic variability. The genus distribution includes tropical South America and Central America south to Honduras. In this study, we evaluate the phylogeographic histories of Proechimys guyannensis and P. cuvieri using cytochrome b, in a densely sampled area in northeastern Amazon where both species are found in sympatry in different environments. For each species, Bayesian and Maximum Likelihood phylogenetic analysis were congruent and recovered similar clades in the studied area. Bayesian phylogenetic analysis using a relaxed molecular clock showed that these clusters of haplotypes diversified during Pleistocene for both species. Apparently, the large rivers of the region did not act as barriers, as some clades include specimens collected from opposite banks of Oiapoque, Araguari and Jari rivers. Bayesian skyline plot analysis showed recent demographic expansion in both species. The Pleistocene climatic changes in concert with the geologic changes in the Amazon fan probably acted as drivers in the diversification that we detected in these two spiny rats. Proechimys cuvieri and P. guyannensis show genetic structure in the eastern part of the Guiana region. Greater genetic distances observed in P. guyannensis, associated with highly structured groups, suggest that more detailed studies of systematics and ecology should be directed to this species.

Domaines: Evolution [q-bio.PE]

Claudia Regina Silva, Camila Cherem Ribas, Maria Nazareth F. da Silva, Rafael Nascimento Leite, François Catzeflis, et al.. The role of Pleistocene climate change in the genetic variability, distribution and demography of Proechimys cuvieri and P. guyannensis (Rodentia: Echimyidae) in northeastern Amazonia. PLoS ONE, 2018, 13 (12), pp.e0206660. ⟨10.1371/journal.pone.0206660⟩. ⟨hal-02948272⟩