Necromys lasiurus (Cricetidae: Sigmodontinae) from open areas of the Atlantic Forest of Rio de Janeiro: Population structure and implications for the monitoring of hantaviruses

ABSTRACT The hairy-tailed bolo mouse, Necromys lasiurus (Lund, 1841), which is typical of the Cerrado (CE), has been recorded in some open areas within the Atlantic Forest (AF) domain of the Brazilian state of Rio de Janeiro (RJ). In the CE, N. lasiurus is a known reservoir of zoonotic agents, and is the reservoir of an orthohantavirus genotype, Araraquara virus (ARAV), the etiological agent of Hantavirus Pulmonary Syndrome (HPS). Given this, the presence of N. lasiurus has potentially negative implications for public health in the state, and therefore it is important to elucidate the origin of its populations in RJ and their connections with populations outside the AF known to carry the ARAV. In the present study we combined phylogenetic and phylogeographic approaches to elucidate the evolutionary history of N. lasiurus populations in RJ, and to test if their dispersal into the AF domain is recent or ancient. These analyses were based on sequences of the mitochondrial Cytochrome b gene, obtained from N. lasiurus specimens from the Atlantic Forest of Rio de Janeiro (AF-RJ), together with all the sequences of this gene available for N. lasiurus in GenBank. In addition to the phylogenetic and phylogeographic analyses, the sequences were used to test among five hypothetical demographic scenarios, proposed to explain the evolutionary history of the hairy-tailed bolo mouse in the state of RJ. The results of all the analyses indicated that populations from AF and the Arid Diagonal (AD) of South America, which includes the CE, diverged in the Late Pleistocene but reconnected in the Holocene. The RJ population (AF-RJ) resulted from this recent genetic admixture among diverging populations from AF and AD. Despite the recent reconnection, no evidence has been found that the AF-RJ N. lasiurus population acts as a reservoir of ARAV, although the continued genetic connectivity with those from AD highlight the need to reinforce the public health monitoring of orthohantavirus in this rodent, especially given the potential spillover of other genotypes. Overall, then, the results of the present study provide important new insights into the evolutionary history of N. lasiurus, which should contribute to the surveillance of orthohantaviruses, and the development of more effective measures for the prevention and control of this zoonosis.