The taxonomic status of the Castelo dos Sonhos Hantavirus reservoir, Oligoryzomys utiaritensis Allen 1916 (Rodentia: Cricetidae: Sigmodontinae)

Abstract

Species of the genus Oligoryzomys are commonly found accross Latin America, and several of them play important rolesas natural reservoirs of Hantaviruses. Here we demonstrate that O. utiaritensis, the natural reservoir of hantavirus Castelodos Sonhos in northwestwern Brazil and previously considered a junior synonym of O. nigripes or O. eliurus, is a validspecies. Morphology, morphometry, karyotyping, and phylogenetic reconstructions based on nuclear (intron 7 of the beta-fibrinogen gene) and mitochondrial (cytochrome b) DNA show that O. utiaritensis differs from O. nigripes and from otherforms of the genus, including the recently described taxon O. moojeni. Oligoryzomys utiaritensis differs in external (whit-ish ventral pelage and tail weakly bicolored) and cranial (incisive foramina never extending posteriorly the alveolus lineof M1) characters from sympatric species. It has the highest diploid number (2n=72) within Oligoryzomys, and is charac-terized by three putative synapomorphies in cytochrome b, and one in intron 7 of beta fibrinogen. We also point to theassignment of Oligoryzomys eliurus as a junior synonym of O. nigripes. Finally, we present phylogenetic analyses of in-trageneric relationships showing that O. utiaritensis is a member of a clade containing Amazonian and Cerrado taxa, including O. moojeni, O. rupestris, and O. delicatus.

Systematics ofOligoryzomys(Rodentia, Cricetidae, Sigmodontinae) from southern Chilean Patagonia, with the description of a new species

“…The interparietal bone is wider than the posterior border of frontals in O. yatesi, whereas Weksler () reported O. flavescens, O. fornesi, O. fulvescens, O. nigripes, and O. stramineus with interparietal strap‐shaped nearly as wide as posterior border of frontals; Agrellos et al. () also shown the interparietal as wide as frontals for O. utiaritensis ; we found the same state for O. longicaudatus (Figure f). The anterodorsal margin of zygomatic plate of O. yatesi is smoothly rounded and very slightly in front of the anterior margin of superior maxillary root of zygomatic arch (Figure g), resembling the morphology of O. microtis and O. utiaritensis, which are much more marked than morphology showed by O. flavescens, O. fornesi, O. fulvescens, O. nigripes, and O. stramineus who show the morphology of O. longicaudatus (Figure h) and O. brendae (Agrellos et al., ; Carleton & Musser, ; Teta et al., ; Weksler, ).…”

“…Interestingly, the Robertsonian fusion is sufficient to generate reproductive isolation and thereby generate new species (Templeton, ), added to the fact that at least for Oligoryzomys spp. the diversification processes have been usually associated with chromosomal changes (see table 3 on Agrellos et al., ). Consequently, based on all former evidence, we propose that the specimens trapped in Harrison and Capitán Aracena islands constitute a new species that we describe in the following section.…”

“…The Cytb sequences of the five specimens of Oligoryzomys sp. nov., as well as those of O. longicaudatus from several localities of the species range and putative O. magellanicus from Río Penitente (Palma et al., ; Weksler & Bonvicino, ), were aligned with other species of the genus obtained from the GenBank following the chain of phylogenetic studies of the genus which have maintained the use of well‐determined specimens assigned to each Oligoryzomys species detailed in Appendix (Agrellos et al., ; Hanson et al., ; Teta et al., ). Aligned sequences were analyzed phylogenetically using maximum likelihood and Bayesian methodology.…”

“…Oligoryzomys was originally included as a subgenus within Oryzomys , but Carleton and Musser () recognized it as a valid genus based on several morphological features including cranial, tooth, and stomach morphology, as well as by its reduced body size, tail longer than head and body, short and broad hind foot, small skull, and a convex interorbital region. Currently, 23 named species have been recognized within the genus as consequence of recent morphological and phylogenetic studies of Oligoryzomys (Agrellos et al., ; Hanson, Utrera, & Fulhorst, ; Palma et al., ; Teta, Jayat, Ortiz, & D'Elía, ; Weksler & Bonvicino, ). However, several innominate forms have been considered as part of taxonomic accounts and phylogenetic studies for the genus (e.g ., Oligoryzomys spB ; O. sp1 ; O. sp2; Carleton & Musser, ; Palma et al., ; Teta et al., ).…”

Advances in cytogenetics of Brazilian rodents: cytotaxonomy, chromosome evolution and new karyotypic data

“…A. Allen, 1916) (2n = 64, FN = 64,66), Oryzomys moojeni Weksler & Bonvicino, 2005 (2n = 70, FN = 72, 74, 76), Oryzomys nigripes (2n = 62, FN = 80-82), Oryzomys stramineus Bonvicino & Weksler, 1998 (2n = 52, FN = 68-70), Oryzomys utiaritensis J. A. Allen, 1916 (2n = 72, FN = 76) (Almeida and Yonenaga-Yassuda 1991, Bonvicino and Weksler 1998, Andrades-Miranda et al 2001a, Agrellos et al 2012, Di-Nizo 2013). …”