Anthropogenic invaders: historical biogeography, current genetic status and distribution range of the “peludo” Chaetophractus villosus (Xenarthra) in Patagonia and Tierra del Fuego, southern South America

POLJAK, SEBASTIÁN; SÁNCHEZ, JULIETA; LANUSSE, LUCAS; LIZARRALDE, MARTA SUSANA

MAMMALIA

WALTER DE GRUYTER & CO

Año: 2020 vol. 0

0025-1461

Chaetophractus villosus was once distributedfrom the south of Bolivia and Paraguay to the northwestof Patagonia, where the species survived in glacial refugia during Pleistocene. After the ice retreated, the species expanded its distribution further south reachingChubut River. In the last two centuries, the species colonized the rest of Patagonia on both sides of the Andes andwas introduced in Tierra del Fuego (TDF) in 1982, whereit expanded its distribution range along 484 km2 until2005. A single mitochondrial Control Region haplotype(HC) was described across Argentine Patagonia based onthe low number of samples. This lack of variability wasexceptional and impressive, taking into account that thenorthern neighboring areas of distribution are consideredancestral due to the haplotype richness. Here, we addednew field and genetic data and compiled recent bibliography to update the biogeography and phylogeographyof the species in southern South America. To explainthe unprecedent lack of genetic variability, we discussedthree main aspects: a historical biogeographic aspectrelated to the natural barriers for the species, a strongstochastic component, and the possible adaptive advantages of the only mitochondrial lineage detected, whosecolonization and acclimatization to the new environmentwere mediated by man. We also estimated that the currentdistribution range in TDF is about 8527 km2.