Marmosa rubra Tate, 1931

Part, Tate’, The Species In, Mexicana’, And, Closely, Mitis’ Sections And Other & Forms, Related, 2010, A Revision Of The Didelphid Marsupial Genus Marmosa, Bulletin of the American Museum of Natural History 2010 (334), pp. 1-83 : 61-64

Marmosa rubra Tate, 1931 Figure 29

Marmosa rubra Tate, 1931: 6 . Type locality

‘‘mouth of Rio Curaray, Province of Oriente,

Ecuador’’ (this locality is actually in Departa-

mento Loreto, Peru; see below). Marmosa rubra: Tate, 1933: 105 . Marmosa [( Marmosa )] rubra: Cabrera, 1958: 25 . Marmosa rubra: Honacki et al., 1982: 23 . Marmosa rubra: Gardner, 1993: 19 . Marmosa rubra: Emmons, 1997: 25 . Marmosa rubra: Eisenberg and Redford, 1999: 62 . Marmosa rubra: Nowak, 1999: 21 . Marmosa rubra: Voss and Jansa, 2003: 75 . Marmosa rubra: Brown, 2004: 68 . Marmosa rubra: Gardner, 2005: 9 . Marmosa rubra: Creighton and Gardner, 2008: 60 . TYPE MATERIAL: The holotype (by original designation, AMNH 71973) is a mature adult (age class 8) female preserved as a skin and skull; although the skin is in good condition, the auditory region is damaged on the left side of the skull.

TYPE LOCALITY: The holotype of Marmosa rubra was collected by Carlos Olalla and Sons (an Ecuadorean family of professional collectors) on 7 December 1925 at a locality they called ‘‘Boca río Curaray’’ (gazetteer entry 226; appendix) in territory historically claimed by Ecuador. Tate’s (1931: 6) verbatim type locality ‘‘mouth of Rio Curaray, Province of Oriente, Ecuador’’ reflects the Olallas’ patriotism, but it is geographically inaccurate because the mouth of the Curaray—a right-bank tributary of the lower Napo —is (and was, de facto, in 1925) in the Peruvian department of Loreto. According to Wiley (in press), the Olallas’ collections from ‘‘Boca río Curaray’’ proba- bly include material collected on both banks of the Curaray and the Napo within a radius of several kilometers around the confluence of those rivers. It is not known exactly where the holotype of M. rubra was taken in this general area.

MORPHOLOGICAL DIAGNOSIS: Midrostral fur pale, usually contrasting sharply with darker fur of crown; dark median rostral stripe present and usually distinct; dark facial mask not extending posteriorly to contact base of ear. Dorsal body pelage usually dull reddish brown (occasionally dark grayish brown washed with dark orange or red); dorsal cover hairs 8–10 mm in length, guard hairs 10–12 mm in length; gray-based ventral pelage conspicuous, usually covering sides of neck, chest, and abdomen (sometimes also extending to the inner parts of arms and legs), with orangish hair tips; self-colored ventral pelage (usually extending as a continuous median strip from chin to anus) yellowish buff or orangish buff. Exposed skin of tail dark brown dorsally from base to tip, indistinctly paler ventrally; caudal scales arranged in spiral pattern; about 16 scales/ cm on dorsal surface at caudal midlength; caudal-scale hairs dark brown and not apparent without magnification; central hair of each caudal-scale triplet about as long as one scale. Gular gland absent. Mammae 3–1– 3 5 7 or 4–1–4 5 9. Lateral and medial carpal tubercles present in mature adult males; medial carpal tubercle short, robust, comma shaped, close to the base of pollex, and not bipartite.

Rostral process of premaxillae long, slightly greater than or equal to I1 height. Orbitosphenoid-alisphenoid suture variable, somewhat longer than or similar to sphenorbital fissure height in lateral view. Supraorbital ridges subparallel or slightly divergent posteriorly, slender, and dorsally reflected in mature adults, not projecting laterally over orbital fossae; postorbital process absent or indistinct; temporal ridges conspicuous, parallel or slightly convergent posteriorly. Palatine fenestrae absent (but tiny asymmetrical palatine perforations occasionally present); posterolateral palatal foramina small, similar in length to M4 (measured at paraconemetacone). Tympanic wing of alisphenoid small and laterally compressed, often somewhat pointed ventrally; medial process of ectotympanic absent or indistinct. I1 hypsodont; crown of I2 usually sharply defined in relation to root; C1 without accessory cusps; preparacrista usually connected to stylar cusp A on M1–M3; stylar cusps D and E usually separated by a distinct notch on M2.

COMPARISONS: Morphological comparisons of Marmosa rubra with other congeneric species treated in this report are provided in the preceding accounts. Brief comparisons with other members of the subgenus Marmosa with which it overlaps geographically in western Amazonia are provided below.

Marmosa rubra is most readily distinguished from M. andersoni by having a dark median rostral streak (absent or indistinct in andersoni ), by usually having a continuous median streak of self-colored ventral fur (absent in andersoni ), by having spirally arranged caudal scales (the caudal scales are both spirally and annularly arranged in andersoni ), by lacking distinct postorbital processes and palatine fenestrae (both present in andersoni ), and by the preparacrista of M1–2 connecting to stylar cusp A (the preparacrista of these teeth connects to styB in andersoni ).

Marmosa rubra is much larger than M. lepida in all measured dimensions (the length of the upper molar series, for example, is 7.1– 7.6 mm in rubra but only 5.6–6.7 mm in lepida ). Qualitative character differences that distinguish these species include the dark median rostral streak (present in rubra , absent in lepida ), distinct postorbital processes (absent in rubra , present in lepida ), a posterior accessory cusp on C1 (absent in rubra , present in lepida ), and the connection of the preparacrista on M1–M2 (to styA in rubra , to styB in lepida ).

Marmosa rubra can be distinguished from M. murina and M. quichua by having a dark median rostral streak (absent in murina and quichua ), by having reddish-brown dorsal fur (the dorsal pelage is grayish brown in murina and quichua ), by lacking a gular gland (present in murina ), by the presence of carpal tubercles in mature adult males (absent in murina and quichua ), by lacking postorbital processes (present in murina and quichua ), by the preparacrista of M1–2 connecting to stylar cusp A (the preparacrista of these teeth connects to styB in murina and quichua ), and by the usual presence of a distinct notch between stylar cusps D and E on M2 (usually absent in murina and quichua ).

GEOGRAPHIC DISTRIBUTION AND SYM- PATRY: The known distribution of Marmosa rubra , the only Amazonian species treated in this report, extends from the Río Mecaya (locality 179; fig. 30) in Departmento Putumayo, Colombia, southward along the eastern Andean piedmont and adjacent lowlands (between 180 m and 730 m elevation) to Hacienda Villa Carmen (locality 225) in Departmento Cusco, Peru. The natural vegetation throughout this region is either lowland or premontane rain forest .

Although the geographic range of Marmosa rubra does not overlap that of any other species reviewed herein, it does overlap the distributions of several distantly related congeners, including M. andersoni , M. lepida , M. murina , and M. quichua . The details of this overlap and lists of localities where M. rubra occurs sympatrically with other species of Marmosa (Marmosa) will be described in subsequent reports.

GEOGRAPHIC VARIATION: We did not observe any noteworthy variation among geographic samples of this species.

TAXONOMIC HISTORY: Marmosa rubra was originally described by Tate (1931) based on the holotype and 11 paratypes. Tate considered M. rubra to be closely related to M. murina , but provided no arguments to support that hypothesis. Later, based on perceived similarities in mammary formulae, inguinal pelage color, caudal features, and supraorbital morphology, Tate (1933) grouped M. rubra , M. murina , M. quichua , and M. tyleriana to form his Murina Section of the Murina Group of Marmosa . A close relationship between M. rubra and M. murina , however, is not supported by recent

analyses of molecular sequence data (e.g., Voss and Jansa, 2003, 2009; see fig. 2). To our knowledge, the validity of Marmosa rubra as a full species of mouse opossum has never been questioned.

SPECIMENS EXAMINED (N 5 44): CO- LOMBIA— Putumayo, Río Mecaya ( FMNH 70969–70977 ). ECUADOR —Province unknown, Huachi ( BMNH 54.268 ). Napo, Puerto Napo (5 Near the River Napo: BMNH 34.9.10.230–34.910.233). Orellana, San José Nuevo (5 San Jose´ : AMNH 68128 ; 5 San José Abajo : AMNH 68129 , 68137– 68139 ), San José de Payamino ( FMNH 124612 ). Pastaza, Montalvo ( FMNH 41452– 41454 , USNM 274577 ), Río Copotaza (5 Río Copataza : FMNH 53348 , 53350 ), Río Pindo (5 Rio Pindo Yaco : FMNH 43181–43183 , USNM 274578 ). Sucumbíos, Marian ( FMNH 124611 ). PERU — Amazonas, Huampami (5 Headwaters of Río Huampami : MVZ 153283 ; 5 [Vicinity of] Huampami ( MVZ 153280 , 153282 , 154759 , 154765 ), Puesto Vigilancia Comaina ( USNM 581941 ). Cusco, Hacienda Villa Carmen ( FMNH 84253 ). Loreto, Boca del Río Curaray ( AMNH 71950 , 71952 , 71953 , 71972 , 71973 [holotype of Marmosa rubra Tate, 1931 ], 71976) .