Systematics of the subgenus of mouse opossums Marmosa (Micoureus) (Didelphimorphia, Didelphidae) with noteworthy records from Paraguay

Abstract

a b s t r a c tThe subgenus Marmosa (Micoureus) Lesson, 1842 includes six species of long-tailed, black masked mouseopossums widely distributed in forested areas of the Neotropics from northern Argentina to Belize. Most of the nominal forms of Marmosa (Micoureus) have not been revised since 1933 and some currently accepted synonymies are in need of revision; similarly distributions of these forms remain for the most part unclear. Herein, we report Paraguayan new and noteworthy locality records for Marmosa (Micoureus), including the first records for the western Dry Chaco region. Specimens were identified to the species level on the basis of morphological and molecular data. In addition, we conducted a phylogenetic analysis that includes sequences of five of the six species currently recognized of Micoureus incorporating a total of 70 sequences of the subgenus. This constitute the most taxonomically and geographically dense phylogenetic analysis of Micoureus. Results show that the most basal dichotomy of the Micoureus clade does not delimit cis-and trans-Andean reciprocally monophyletic groups, rending the cis group paraphyletic to the single trans-species included, suggesting that the colonization of the western (trans) side of the Andes was a relatively late event in the biogeographic history of Micoureus. In addition, the phylogenetic analysis shows that additional taxonomic work is much needed to clarify the number of distinct biological units, either species or subspecies, within Micoureus.

Additions to the Paraguayan mammal fauna: the first records of two marsupials (Didelphimorphia, Didelphidae) with comments on the alpha taxonomy of Cryptonanus and Philander

“…Our genealogy shows that C. chacoensis is not phylogeographically structured in Paraguay, even when there is considerable variation in body size with smaller specimens inhabiting the dry habitats and larger individuals in the Atlantic Forest (de la Sancha per obs.). A similar morphological pattern has been observed for Marmosa constantiae with smaller specimens west of the Paraguay River (de la Sancha et al 2012); however, small sample sizes of M. constantiae preclude a robust test of this pattern, although Smith et al (2012) suggest specimens of M. constantiae from both sides of the Paraguay River are comparable in size. Understanding the cause of this presumptive pattern of morphological variation along this environmental gradient is a valuable question to address.…”

“…However, what is known for most species is little more than preliminary data on habitat preference and activity patterns, with rough approximations to their distributions (D'Elía et al 2008). In addition, the large list of new species records reported in the last decade (de la Sancha et al 2007, D'Elía et al 2008, Percequillo et al 2008, Stevens et al 2010, de la Sancha et al 2011, Smith et al 2011, de la Sancha et al 2012) demonstrates that much is still unknown about Paraguayan mammals. As such, this reiterates the need and importance of continued basic mammalogy work, including field collections, in Paraguay.…”

“…Didelphis albiventris is found throughout Paraguay and is the only large marsupial to be found throughout the country, while Didelphis aurita (Wied-Neuwied 1826) is restricted to eastern Paraguay (Cerqueira and Tribe 2008 (Teta et al 2009). While some other marsupial species have been reported on both sides of the Paraguay River (e.g., Monodelphis kunsi, Monodelphis domestica, and Marmosa constantiae) (de la Sancha et al 2007(de la Sancha et al , 2012 these are found Figure 6 Majority-rule consensus resulting from the Bayesian analysis based on the first 801 bases of the cytochrome b gene of Cryptonanus. Numbers indicate posterior probability values of the nodes at their right.…”

Patterns of small mammal diversity in fragments of subtropical Interior Atlantic Forest in eastern Paraguay

“…It is improbable that a few decades of anthropogenic change resulted in a complete loss of all endemics, while considerably smaller coastal, smaller fragments maintained these endemic AF species. Many, if not all of the species found in the forest fragments of PY could be considered matrix tolerant, edge, or generalist species in coastal AF (Pires et al 2002, Pardini 2004, Pardini et al 2005, Umetsu and Pardini 2007) with a few exceptions like Juliomys pictipes and Marmosa paraguayana (de la Sancha et al 2009a(de la Sancha et al , 2012. The patterns found in the interior of the largest remnant in this study, Mbaracayú, are similar to other contiguous high-quality forest like the Amazon.…”

An annotated checklist of the mammals of Paraguay

“…Recent works have incorporated both morphological and genetic evidence to improve our understanding of the distribution and systematics of Paraguayan marsupials (Voss et al 2005;de la Sancha et al 2007;Teta et al 2009;de la Sancha et al 2012;Smith et al 2012;Martínez-Lanfranco et al 2014;Smith and Owen 2015;de la Sancha and D'Elía 2015). Five species of marsupials have been reported for Paraguay for the first time since 2005.…”