Rediscovery and redescription of Marmosops handleyi (Pine, 1981) (Didelphimorphia: Didelphidae), the least known Andean slender mouse opossum

DÍAZ-N., J.; GÓMEZ-LAVERDE, M.; SÁNCHEZ-GIRALDO, C. 2011. Rediscovery and redescription of Marmosops handleyi (Pine, 1981) (Didelphimorphia: Didelphidae), the least known Andean slender mouse opossum. Mastozoología Neotropical 18(1):45-61.

Abstract. Marmosops handleyi was briefly described in 1981 based on two specimens collected in 1950 in the northern Andes of Colombia. Until now there have been no additional reported records for this species, and knowledge about its taxonomy, ecology, natural history and evolutionary relationships is deficient. Aiming to assess its current distribution, we searched for this species at four localities in the northern part of the Colombian Cordillera Central, where we collected the new material on which this report is based. Morphological comparisons with a sympatric congeneric species herein identified as M. caucae, revealed new external and craniodental characters that we use to redescribe M. handleyi. Our phylogenetic analysis groups M. handleyi as the sister taxon of a clade of small-bodied forms (M. parvidens +  M. pinheiroi), and a basal polytomy includes M. caucae (a Colombian taxon currently synonymized with M. impavidus) and other large-bodied forms. Finally, a reassessment of M. handleyi’s current conservation status suggests that the species should be transferred from Critically Endangered (CR) to Endangered (EN) IUCN category based on our discovery of additional extant populations.