Small Mammals Of The Mayo River Basin In Northern Peru, With The Description Of A New Species Of Sturnira (Chiroptera: Phyllostomidae) Author Velazco, Paúl M. Division of Vertebrate Zoology (Mammalogy) American Museum of Natural History Author Patterson, Bruce D. Integrative Research Center Field Museum of Natural History text Bulletin of the American Museum of Natural History 2019 2019-04-05 2019 429 1 69 journal article 0003-0090 Neacomys spinosus (Thomas, 1882) VOUCHER MATERIAL: Waqanki : 1 adult female ( MUSM 39280 ), 1 adult male ( FMNH 203672 ) ; see table 23 for measurements. IDENTIFICATION: Neacomys spinosus was considered the most widespread species of Neacomys (e.g., Patton et al., 2000 ; Hice and Velazco, 2012 ; Weksler and Bonvicino, 2015a ) until the taxonomy and systematics of the species was reviewed and its limits were reassessed by Hurtado and Pacheco (2017) . The latter authors restricted the distribution of N. spinosus to montane cloud forests of the Peruvian departments of Amazonas , San Martín , and Huánuco across an elevational range that extends from 1127 to 2100 m . Neacomys spinosus is distinguished from other congeneric species by the following combination of characteristics: dorsal fur reddish; ventral fur pale white with gray bases; carpal vibrissae short; carpal and metatarsal patches always present; tail long; supraorbital beads moderately developed; alisphenoid strut present; condylar process large and slim; procingulum of M1 anteriorly flattened; posteroloph short; and protoflexus in M1 deep ( Hurtado and Pacheco, 2017 ). Our specimens conform to this emended description of the species, and measurements fall within the range of size variation previously documented. REMARKS: At Mayo River basin, Neacomys spinosus was captured near a small stream. Our specimens were captured at the Waqanki locality that is at an elevation of 970 m , somewhat lower than the minimum elevation ( 1127 m ) previously reported for the species by Hurtado and Pacheco (2017) . Lareschi and Velazco (2013) reported the mites Gigantolaelaps intermedia , Laelaps boultoni , and Laelaps neacomydis from our specimens.