Species diversity in the Monodelphis brevicaudata complex (Didelphimorphia: Didelphidae) inferred from molecular and morphological data, with the description of a new species

The Monodelphis brevicaudata complex comprises the short-tailed opossum M. brevicaudata and allied forms that inhabit northern and middle South America. We studied the systematics of this complex through a combination of molecular (cytochrome b and 16S rDNA) and morphological (external and craniodental) characters. Our evidence shows that M. brevicaudata as currently recognized comprises three different species: M. brevicaudata; Monodelphis touan, resurrected from the synonymy of M. brevicaudata; and a new species described here. Other species formally recognized in the M. brevicaudata complex include Monodelphis palliolata, Monodelphis glirina, Monodelphis maraxina, Monodelphis domestica, and two additional forms for which formal descriptions are still missing.