Glironia venusta Thomas, 1912

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 : 17-20

Glironia venusta Thomas, 1912

VOUCHER MATERIAL (TOTAL = 1): Quebrada Vainilla (LSUMZ 28421).

OTHER INTERFLUVIAL RECORDS: None.

TABLE 2

IDENTIFICATION: As currently understood, Glironia venusta ranges across much of Amazonia but remains known from only a few specimens ( Barkley, 2008; Ardente et al., 2013). Among the handful that we were able to examine for this report were the holotypes of two nominal species— aequatorialis Anthony, 1926, and criniger Anthony, 1926 —that have long been regarded as junior synonyms of venusta . Whereas the type localities of aequatorialis (Boca Río Lagartococha, on the Peruvian-Ecuadorian frontier) and criniger (Boca Río Curaray, in Loreto department) are both north of the Amazon, 3 the type locality of venusta (Pozuzo, in Pasco depart-

3 See Wiley (2010) for information about these historically important localities. ment) is south of the Amazon. In addition to these and our single specimen from Quebrada Vanilla, we examined a fourth specimen, from eastern Ecuador.

Although Barkley (2008) said that LSUMZ 28421 was an adult, it is really a subadult with a still incompletely erupted P3 on each side. The immaturity of this specimen plausibly explains why it is smaller than the others we measured (table 3) in several cranial dimensions subject to postweaning growth (e.g., CBL, ZB, PB), but not in age-invariant molar dimensions (LM, M1–3, WM3). We did not note any conspicuous craniodental differences among these specimens, but the tip of the tail is abruptly white for about 2 cm in LSUMZ 28421, a marking that is also present

TABLE 3

on BMNH 12.1.15.7 ( Thomas, 1912b), but not in any of the specimens we examined from the left (“north”) bank of the Amazon, which all have grayish or brownish tail tips.

Preliminary genetic data suggest that distinct haplotypes of Glironia venusta occupy opposite banks of the Amazon. Patton et al. (1996) obtained 1140 bp of cytochrome b from a single specimen (INPA 2570) collected on the upper Rio Urucu, a right-bank tributary of the upper Amazon (Solimões) in western Brazil. This sequence differs by about 6% (uncorrected) from two large fragments (both>500 bp) that we obtained from the left-bank holotypes of criniger (AMNH 71394) and aequatorialis (AMNH 71395); by contrast, the latter two sequences differ from one another by just a single base-pair substitution (an uncorrected distance of just 0.2%). Although it might make some sense in the light of these results to recognize two subspecies, G. v. criniger (including aequatorialis) on the north bank and G. v. venusta on the south bank, we are reluctant to formalize any taxonomic conclusions on such an inadequate basis. Nevertheless, the trivial genetic distance between the two left-bank specimens does tend to support the conclusions of previous taxonomists that the allegedly diagnostic morphological differences between criniger and aequatorialis reported

by Anthony (1926) are nothing more than intraspecific variation.

ETHNOBIOLOGY: The Matses have no definite knowledge of this species, and therefore do not have a name for it or any particular beliefs about it.

MATSES NATURAL HISTORY: The Matses have no knowledge of the appearance or behavior of this species.

REMARKS: According to Barkley (2008), LSU 28421 was captured at night in a mist net set for bats in primary forest. Local habitats at the capture site, which is not subject to seasonal inundation, were described by Robbins et al. (1991).

OTHER SPECIMENS EXAMINED (TOTAL = 3): Ecuador — Pastaza, Montalvo (FMNH 41440). Peru — Loreto, Boca Río Curaray (AMNH 71394). Peru (Loreto) or Ecuador (Orellana)— Boca Río Lagartococha (AMNH 71395).