Molecular discrimination of pouched four-eyed opossums from the Mamirauá Reserve in the Brazilian Amazon

Abstract

Previous cytochrome B (CytB) mtDNA studies have suggested four species for the opossum genus Philander (four-eyed opossums), three (P. mcilhennyi, P. andersoni and P. opossum) from the Amazon and one (P. frenata) from the Brazilian Atlantic forest. During a faunal survey nine specimens of Philander sp. and four of Didelphis marsupialis were collected in the Mamirauá Sustainable Reserve, Amazonas State, Brazil. Preliminary analyses based on morphology and geographical distributions were not conclusive, suggesting that Philander specimens could belong to either P. andersoni or P. opossum. In order to elucidate the relationship of this taxon to the remaining Amazonian taxa, seven Philander and two Didelphis specimens animals were sequenced for the cytB mtDNA gene and compared to other previously studied taxa. The maximum likelihood (ML), neighbor-Joining (NJ) and maximum parsimony (MP) consensus bootstrap trees depicted six groups: Didelphis., P. frenata, P andersoni, P. mcilhennyi, P.o. opossum and Philander sp. and Philander canus in a common assemblage supported by significant bootstrap values, suggesting that the Philander sp. from Mamiraua in fact belongs to the species Philander canus.

A Revision ofPhilander(Marsupialia: Didelphidae), Part 1:P. quica,P. canus, and a New Species from Amazonia

“…Remarks: Specimens that we refer to Philander pebas were among those previously identified as P. opossum quica by Hershkovitz (1997), as P. opossum canus by Patton et al (2000), as P. opossum by Woodman et al (1991) and Hice and Velazco (2012), and as P. canus by Nunes et al (2006). Although we were unable to examine any of the specimens from northeastern Peru identified as P. opossum by Díaz (2014), we suspect that most of them are P. pebas.…”

“…Of the five that we were able to examinethe others having been returned to Brazil-four (MVZ 190343-190346) are P. pebas; only one (MVZ 190347, from the state of Acre, near the Peruvian border) is actually P. canus. The central Amazonian specimens that Nunes et al (2006) identified as P. canus are also examples of P. pebas. 11 The only other material of P. canus that we have seen from the Brazilian Amazon (besides the MVZ specimen from Acre) is a small series collected many years ago along the lower Rio Madeira (in Amazonas state) and a single specimen from the upper Madeira (in Rondônia).…”

“…Another record of Philander pebas from seasonally flooded forest is based on the specimens of Philander "canus" analyzed by Nunes et al (2006). These specimens, which we reidentified as P. pebas, were collected in the Mamirauá Sustainable Development Reserve, a protected area consisting entirely of várzea at the confluence of the Rio Japurá and the upper Amazon (Solimões).…”

“…This hypothesis, implying reproductive continuity among populations spanning numerous zoogeographic barriers (mountains, rivers, open habitats) and many thousands of kilometers, persisted until Gardner and Patton (1972) reported sympatry between two phenotypically distinguishable species in western Amazonia. Subsequent publications have reported other examples of sympatry between two kinds of Amazonian Philander (Hutterer et al, 1995;Patton et al, 2000;Hice and Velazco, 2012), and DNA-sequencing studies have discovered deep genetic divergence-equivalent to that seen between sympatric Amazonian taxa-among allopatric forms that have long been considered synonyms or subspecies of P. opossum (see Patton and da Silva, 1997;Nunes et al, 2006;Chemisquy and Flores, 2012).…”

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

“…Importantly, and independently of the taxon to which Paraguayan populations has been referred, all authors recognize a single species in Paraguay, currently considered to be P. frenatus restricted to eastern Paraguay da Silva 2008, Chemisquy andFlores 2012). Here, we (Patton and Da Silva 1997, Nunes et al 2006, Agrizzi et al 2012, Chemisquy and Flores 2012 (Gardner 2008). Our specimens are genealogically closely related to specimens referred to P. o. canus by Chemisquy and Flores (2012), and we refer them to this form.…”