Genetic diversity of wild populations of the grey short-tailed opossum,Monodelphis domestica(Didelphimorphia: Didelphidae), in Brazilian landscapes

Abstract

The characterization of the different taxa of the highly diverse genus Monodelphis is poorly understood, as is the case of their distribution. Historically, taxonomic studies of Monodelphis have been restricted to a few or single species, whereas molecular approaches have been used for estimating phylogenetic relationships between species. We carried out phylogenetic analyses of 14 Monodelphis species, including Monodelphis domestica, based on cytochrome b mitochondrial DNA sequences. Forty-five complete (1149 bp) sequences of this gene were obtained from 39 specimens of M. domestica collected in 23 localities of the Brazilian Cerrado, Pantanal, and Caatinga morphoclimatic domains; one of Monodelphis umbristriata, two of Monodelphis americana, and two of Monodelphis dimidiata. A total of 72 haplotypes were analyzed, 48 only in M. domestica. Analyses were carried out in conjunction with 46 other sequences retrieved from GenBank, including M. domestica, Monodelphis brevicaudata, Monodelphis glirina, Monodelphis emiliae, Monodelphis peruviana, Monodelphis osgoodi, Monodelphis handleyi, Monodelphis kunsi, Monodelphis americana, Monodelphis dimidiata, Monodelphis iheringi, Monodelphis reigi, andMonodelphis adusta, with six other different didelphid species used as outgroups. Maximum likelihood and Bayesian inference were similar in depicting phylogenetic relationships of different Monodelphis taxa. Two clades of M. domestica were defined on the basis of these results. Genetic distance estimates ranged from 3.2% to 6.2% between these clades of M. domestica. Population analyses were carried out to infer the likely demographic scenarios and the relationship between M. domestica haplotypes. Median-joining and spatial analyses showed two populations related to different morphoclimatic domains (Cerrado/Pantanal and Caatinga). These results indicate a population structure in M. domestica and the possibility that this taxon might represent a species complex.

The second known specimen of <i>Monodelphis unistriata</i> (Wagner) (Mammalia: Didelphimorphia), with redescription of the species and phylogenetic analysis

“…Indeed, one of the most probable phylogenetic positions of G. venusta is as sister to the rest of the didelphid crown group ). The monophyly and internal relationships of Monodelphis are in partial agreement with previous phylogenetic analyses performed on the genus (e.g., Solari 2010;Caramaschi et al 2011;Solari et al 2012). Our combined analysis strongly supports the genus Monodelphis as monophyletic (Fig.…”

“…Although the evidence used to determine the phylogenetic position of M. unistriata is limited to some external characters and a fragmentary skull, our phylogenetic inferences based on combined characters suggest that there is a close relationship between M. unistriata and M. iheringi. Although both species have dorsal stripes (but in M. unistriata only a single one), this trait is also shared with M. theresa (sister of M. scalops in this analysis and in the topology recovered by Solari et al 2012), M. americana, and M. umbristriata (Miranda Ribeiro) (the last two species not included in this analysis but recovered as sister species by Caramaschi et al 2011), and M. gardneri (sister of M. americana according to Solari et al 2012). Despite the poor degree of phylogenetic relationship recovered (Fig.…”

“…In addition to the differences in pelage, previously reported (e.g., Massoia et al 2000;Pine & Handley 2008), cranial morphology of adult male M. dimidiata differs in several respects from that of adult male M. sorex as understood by us (e.g., M. dimidiata has a much greater interorbital constriction than M. sorex; see table 1 for additional characters). Recent published data also suggest a species complex for M. domestica (Caramaschi et al 2011), with two clades in Brazil. Specimens we examined of these apparent taxa (see Appendix 1) come from southwestern Brazil, Paraguay, and northern Argentina, which represent areas closely associated with the Cerrado and Pantanal ( clade A in Caramaschi et al 2011) and which include the type locality (Cuiabá, Brazil) for M. domestica, and thus our voucher specimens correspond to M. domestica sensu stricto.…”

“…Recent published data also suggest a species complex for M. domestica (Caramaschi et al 2011), with two clades in Brazil. Specimens we examined of these apparent taxa (see Appendix 1) come from southwestern Brazil, Paraguay, and northern Argentina, which represent areas closely associated with the Cerrado and Pantanal ( clade A in Caramaschi et al 2011) and which include the type locality (Cuiabá, Brazil) for M. domestica, and thus our voucher specimens correspond to M. domestica sensu stricto. Similarly, our voucher specimens of M. brevicaudata come principally from southern Venezuela, and, according to the recent study by Pavan et al (2012), the M. brevicaudata of authors is a species complex, with M. brevicaudata sensu stricto being found this region.…”

Subsidies for a poorly known endemic semiarid biome of Brazil: non-volant mammals of an eastern region of Caatinga

“…This species is widely distributed in Brazil, mainly in open areas east from the southern Amazon basin, through central, eastern, and southern Brazil (Gardner 2008). Monodelphis domestica varies widely in body size and color pattern with geography, and it likely represents a species complex (Caramaschi et al 2011). Thirty-four individuals were captured in two sectors, 33 in Nossa Senhora da Glória and 1 road-killed in Canindé de São Francisco, Sergipe state; we prepared six specimens.…”