Mammalian Diversity And Matses Ethnomammalogy In Amazonian Peru Part 5. Rodents Author Voss, Robert S. Author Fleck, David W. Author Jansa, Sharon A. text Bulletin of the American Museum of Natural History 2019 2024-04-18 2024 466 1 180 http://dx.doi.org/10.5281/zenodo.5414895 journal article 10.5281/zenodo.5414895 0003-0090 Scolomys ucayalensis Pacheco, 1991 VOUCHER MATERIAL ( N = 16): Jenaro Herrera ( AMNH 276715; MUSM 5474 [ holotype ], 23820, 23821), Nuevo San Juan ( AMNH 272668, 272686, 272697, 272706, 272708, 272721; MUSM 13356, 13357, 13358, 13359, 13360, 13361). Although we have not examined the specimens that Medina et al. (2015) reported from Quebrada Lobo, Quebrada Betilia, Quebrada Pantaleón, and Quebrada Sábalo, we assume that they were correctly identified by comparisons with S. melanops , which those authors also reported from the latter three sites. Additional material, possibly corresponding to this species, was reported by Valqui (2001) from San Pedro , but we have not seen his specimens. FIG. 36. Lateral mandibular views of Scolomys melanops ( A , MUSM 23822) and S. ucayalensis ( B , MUSM 13360). Vertical arrows indicate the position of the lower incisor root. Note that the mental foramen ( mf ) is laterally exposed in S. ucayalensis but it is usually concealed in S. melanops . UNVOUCHERED OBSERVATIONS: None. IDENTIFICATION: The type locality of Scolomys ucayalensis is Jenaro Herrera, and neither the topotypic material we examined nor any of our specimens from Nuevo San Juan differ in any essential feature from the subadult holotype . Additionally, our direct comparisons of this Peruvian material with seven paratypes ( MVZ 183165–183171) of S. juruaense Patton and da Silva, 1995 , support the conclusion of Gómez-Laverde et al. (2004) that the latter name is a junior synonym. Diagnostic differences between this species and sympatric S. melanops are described in the preceding account. Although specimens identified as Scolomys ucayalensis have been reported from scattered localities north of the Amazon by various authors (e.g., Gómez-Laverde et al., 2004 ; Brito and Arguero, 2012 ; Díaz, 2020 ), we have not personally examined any, and some of these identifications do not seem plausible. For example, the Ecuadorean specimens reported as S. ucayalensis by Brito and Arguero (2012) appear to be S. melanops based on the accompanying cranial photographs and measurements (especially least interorbital breadth). As mentioned previously, molecular data and karyotypes would provide welcome support for species recognition in future revisionary research with Scolomys . ETHNOBIOLOGY: The Matses do not recognize this species and so have no particular beliefs about it. MATSES NATURAL HISTORY: The Matses have no definite knowledge of this species. REMARKS: Fifteen specimens of Scolomys ucayalensis are accompanied by habitat data from our region. Twelve of these (80%) were taken at Nuevo San Juan in Sherman traps set on the ground in a variety of sheltered situations (under fallen trunks, inside hollow logs, beneath leafy understory vegetation, etc.) in well-drained primary forest on hillcrests, on hillsides, and in moist valley bottoms. Two specimens captured in pitfalls at Jenaro Herrera, however, were taken in swampy primary forest and another was taken in a pitfall in secondary vegetation at the same locality. In western Brazil , Patton et al. (2000) captured 23 specimens , all of them on the ground in primary well-drained (terra firme) forest.