Phylogeny of Marmosops and the occurrence of Marmosops pinheiroi (Pine, 1981) (Didelphimorphia, Didelphidae) in the Cerrado savanna of Maranhão, Brazil.

The present study reviews the phylogeny of the genus Marmosops and expands the geographic range of Marmosops pinheiroi to the Brazilian State of Maranhão. Five specimens of M. pinheiroi were collected from the Inhamum Municipal Environmental Protection Area in Caxias, Maranhão. Total DNA was extracted and the mitochondrial cytochrome b gene was sequenced in an ABI PRISM 3500. Additional sequences of Marmosops were obtained from GenBank for specimens from southeastern and northeast Brazil and the northern Amazon Forest. The results of the analysis indicated that M. incanus and M. paulensis form a well-supported clade, and that M. pinheiroi, M. pakaraimae, and M. parvidens are sister groups, with 71% support. The M. pinheiroi specimens from different regions grouped with high bootstrap values (99 and 100%). Interspecific genetic divergence varied from 8.3 to 21.5%, while intraspecific divergence ranged from 0.2 to 6.3% in M. pinheiroi, 0.3 to 2.9% in M. parvidens, and 0.4 to 6.9% in M. incanus. Given the taxonomic complexity of the genus, the results of the present study offer important insights into the taxonomic status of M. pinheiroi, as well as extend its known distribution 670 km south and east to the Brazilian State of Maranhão.