Marmosa (Micoureus) rutteri Thomas, 1924

Voss, Robert S., Fleck, David W. & Jansa, Sharon A., 2019, Mammalian Diversity And Matses Ethnomammalogy In Amazonian Peru Part 3: Marsupials (Didelphimorphia), Bulletin of the American Museum of Natural History 2019 (432), pp. 1-89 : 31-32

Marmosa (Micoureus) rutteri Thomas, 1924

VOUCHER MATERIAL (TOTAL = 6): Nuevo San Juan (AMNH 273164; MUSM 11055, 11063, 15315, 15316), Orosa (AMNH 74087).

OTHER INTERFLUVIAL RECORDS: None that can be confidently associated with this species.

IDENTIFICATION: As explained in the preceding account, this is the species that Patton et al. (2000) called Micoureus regina , but their usage is taxonomically indefensible. As those authors noted, regina is based on a specimen collected in the Magdalena Valley of Colombia, so it seems biogeographically improbable that the name could validly apply to an Amazonian taxon. Additionally, the type of regina (BMNH 98.5.15.4, an old adult male) does not closely resemble any Amazonian woolly mouse opossum that we have seen. Among other traits that do not fit the present species, the dorsal fur of BMNH 98.5.15.4 is redder (near Prout’s Brown according to Tate [1933: 83], who saw the type when it was less than 40 years old), the upper molars are smaller (LM = 8.1 mm), and the postprotocristae are short. Like Tate (1933), we restrict the application of Marmosa regina to the holotype, and we reject the application of this name to any of the Amazonian nominal taxa treated as subjective junior synonyms or subspecies by Gardner (1993, 2005).

According to Patton et al. (2000), the nextoldest name for this species is Marmosa germana Thomas, 1904 , which was treated as a synonym of M. regina by Gardner (1993), but as a valid subspecies of M. regina by Gardner (2005) and by Gardner and Creighton (2008). However, the type of germana (BMNH 80.5.6.77, an adult female from eastern Ecuador; Thomas, 1904b) more closely resembles the species that Patton and his colleagues called M. demerarae than the species that they called M. regina . Among other traits that do not match the present species, BMNH 80.5.6.77 has completely gray-based ventral fur; a long (30 mm), fluffy-furred tail base; and short postprotocristae. Unpublished DNA sequence data (Voss et al., in preparation) suggest that M. germana is a distinct species, restricted to the left (north) bank of the upper Amazon.

Thomas (1924) described Marmosa rutteri as a valid species, but Tate (1933: 81) considered rutteri to be a subspecies of M. germana , and most subsequent authors have considered rutteri to be a junior synonym of germana (now usually ranked as a subspecies of regina ; e.g., by Gardner, 2005; Gardner and Creighton, 2008). In fact, M. rutteri is a distinct species with the diagnostic traits listed in table 8, and analyses of DNA sequence data (Voss et al., in prep.) suggest that it is more closely related to M. rapposa and other extralimital species than to M. germana . The holotype (BMNH 24.2.22.67, an adult male) is from Tushemo, on the right bank of the upper Ucayali. As recognized in this report, the species is widely distributed in western Amazonia, but different haplogroups are found north and south of the Amazon; the specimens listed below, which include all of those with measurement data summarized in table 7, are from south of the Amazon.

ETHNOBIOLOGY: The Matses do not distinguish this species from other pouchless, longtailed, black-masked species of small opossums (all known as chekampi; see the account for Marmosa , above) and therefore have no particular beliefs about it.

MATSES NATURAL HISTORY: The Matses have no definite knowledge of this species.

REMARKS: Of our four specimens from Nuevo San Juan, one was captured by hand inside a Matses house, one was trapped on top of a fallen log in primary upland forest, one was shot from a tree (at an unrecorded height) in primary upland forest, and one was taken by hand inside a hollow tree at the edge of the Río Gálvez.

OTHER SPECIMENS EXAMINED (TOTAL = 84): Brazil — Acre, Igarapé Porongaba (MVZ 190332), Nova Vida (MVZ 190333) ; Amazonas, Boa Esperança (MVZ 190330, 190331), Igarapé Nova Empresa (MVZ 190321, 190323–190325), opposite Altamira (MVZ 190328, 190329), Penedo (MVZ 190319, 190320), Seringal Condor (MVZ 190326). Colombia — Caquetá, Tres Troncos (FMNH 70964–70966). Ecuador — Napo, San José de Payamino (FMNH 124613). Peru — Amazonas, La Poza (MVZ 157629), mouth of Río Cenepa (AMNH 98712), vicinity of Huampami (MVZ 153278, 154749, 154751, 154755, 154758, 154762, 154764, 154766, 157628, 157630, 157631), vicinity of Kayamas (MVZ 153281) ; Ayacucho, Santa Rosa on Río Santa Rosa (LSUMZ 15674) ; Cuzco, Quincemil (FMNH 75100) ; Loreto, Boca Río Curaray (AMNH 71951, 71956, 71958, 71964, 71966, 71968, 71975, 72010), Otorongo (MUSM 33443), Pampa Chica (FMNH 87118), San Antonio (AMNH 98655), San Jerónimo (BMNH 28.5.2.231–28.5.2.241; FMNH 46110, 46111), Sarayacu (AMNH 76302, 76303), El Triunfo (TTU 124799), Yurimaguas (FMNH 19635) ; Madre de Dios, Blanquillo (MUSM 8399), Reserva Cuzco Amazónico (KU 144091, 144093, 144095, 144100, 144102, 144107, 144110, 144111; MUSM 6083, 6086–6088, 6090–6092, 6100, 6101) ; Pasco, San Pablo (AMNH 230019, 230021) ; Ucayali, Tushemo (BMNH 24.2.22.67 [holotype]), Yarinacocha (FMNH 55467). Peru (Loreto) or Ecuador (Orellana) — Boca Río Lagartococha (AMNH 72008, 72009)