Marmosa (Micoureus) constantiae Thomas, 1904

Voss, Robert S., 2022, An Annotated Checklist Of Recent Opossums (Mammalia: Didelphidae), Bulletin of the American Museum of Natural History 2022 (455), pp. 1-77 : 16

Marmosa (Micoureus) constantiae Thomas, 1904

TYPE MATERIAL AND TYPE LOCALITY: BMNH 3.7 .7.157, the holotype by original designation, consists of the skin and skull of an adult male collected at “Chapada” (= Santa Ana de Chapada : 15.43° S, 55.75° W; 800 m), Mato Grosso state, Brazil .

SYNONYMS: domina Thomas, 1920; mapiriensis Tate, 1931.

DISTRIBUTION: As currently recognized (see Remarks), Marmosa constantiae occurs from the foothills of the Andes (below about 1100 m) in eastern Peru and eastern Bolivia eastward across Amazonia and the Cerrado to central Brazil; mtDNA sequencing results (see Remarks) suggest that the range of this species does not extend north of the Amazon nor east of the Xingu ( Silva et al., 2019: fig. 5; Voss et al., 2020: fig. 2).

REMARKS: The name Marmosa constantiae has long been misapplied to a superficially similar congener, M. rapposa , that also occurs in Mato Grosso and eastern Bolivia (see below). Previous reports of M. constantiae from Argentina ( Flores et al., 2007) and Paraguay ( de la Sancha et al., 2012; Smith and Owen, 2015) likewise appear to have been based on specimens of M. rapposa . As recognized by Silva et al. (2019) and Voss et al. (2020), M. constantiae is geographically variable in coloration: whereas Cerrado populations have pale dorsal fur, broadly self-yellow underparts, and parti- colored (white-tipped) tails, rainforest populations are darker dorsally and have mostly gray-based ventral fur and all-dark tails ( Voss et al., 2019). The rainforest phenotype of M. constantiae is difficult to distinguish morphologically from M. germana (a distantly related congener that occurs north of the Amazon; Voss and Giarla, 2021), so currently recognized range limits are based, in part, on sequencing results rather than examined specimens. Phylogenetic analyses of multilocus sequence data recover M. constantiae and M. demerarae as sister taxa (Voss et al., 2020), and comparisons of sequenced specimens suggest that these taxa are morphologically diagnosable ( Silva et al., 2019).