Oligoryzomys utiaritensis (J. A. Allen, 1916)

Don E. Wilson, Russell A. Mittermeier & Thomas E. Lacher, Jr, 2017, Cricetidae, Handbook of the Mammals of the World – Volume 7 Rodents II, Barcelona: Lynx Edicions, pp. 204-535 : 434

437.

Utiariti Pygmy Rice Rat

Oligoryzomys utiaritensis

French: Colilargo d'Utiariti / German: Utiariti-Zwergreisratte / Spanish: Rata arrocera pigmea de Utiariti

Other common names: Utiariti Colilargo

Taxonomy. Oryzomys (Oligoryzomys) utiaritensisJ. A. Allen, 1916 , Utiarity, Papagaia River, Matto Grosso, Brazil.

Until recently, O. utiaritensis was synonymous with O. nigripes . Monotypic.

Distribution. From SW Para to NW Mato Grosso states, C Brazil.

Descriptive notes. Head-body 78-104 mm, tail 103-135 mm, ear 13-18 mm, hindfoot 19-26 mm; weight 14-32 g. Upperparts of the Utiariti Pygmy Rice Rat are clay-colored, finely line with black-tipped hairs over back and nearly pure clay hairs on sides; front of head and nose are darker and slightly grayish; venter is whitish, with white hair tips and gray bases; ventral and lateral pelage is well-defined; upper surfaces of feet are paler, about flesh-colored; soles are dark brown; ears are large, light brown, and nearly naked; and tail is longer than headbody length, finely annulated, unicolored or weakly bicolored light brown, and nearly naked, with short, bristly grayish hairs on apical part. Skull has long incisive foramina, with posterior borders reaching or almost reaching alveolus of M' but never extending posteriorly.

Habitat. Secondary semideciduous forest associated with corn and soy plantations, eucalypt plantations with herbaceous vegetation, very altered vegetation (semideciduous forest) near plantations, and gallery forests at elevations of 110-570 m.

Food and Feeding. The Utiariti Pygmy Rice Rat is quite likely granivorous, judging by habitats it occurs in.

Breeding. No information.

Activity patterns. No information.

Movements, Home range and Social organization. No information.

Status and Conservation. Not assessed on The IUCN Red List. Association with corn and soy plantation might indicate that the Utiariti Pygmy Rice Rat is of Least Concern. Because major rodent population declines were recently reported from Cerrado ecoregion,its conservation status should carefully be evaluated.

Bibliography. Agrellos et al. (2012), Allen (1916), Bonvicino, Oliveira & D'Andrea (2008), Caceres, Carmignotto et al. (2008), Caceres, Napoli et al. (2010), Di-Nizo et al. (2015), Emmons (2009), Gonzélez-Ittig et al. (2014), Leite & Patterson (2016b), Napoli & Caceres (2012), Nunes et al. (2008), da Rosa et al. (2011), Santos-Filho et al. (2012), Weksler & Bonvicino (2015b), Zimbres et al. (2017).

Figures

420. Western Amazonian Rice Rat (Hylaeamys perenensis), 421. Yungas Rice Rat (Hylaeamys yunganus), 422. Azara’s Rice Rat (Hylaeamys megacephalus), 423. Tate’s Rice Rat (Hylaeamys tatei), 424. Sowbug Rice Rat (Hylaeamys oniscus), 425. Bolivian Rice Rat (Hylaeamys acritus), 426. Atlantic Forest Rice Rat (Hylaeamys laticeps), 427. Fulvous Pygmy Rice Rat (Oligoryzomys fulvescens), 428. Costa Rican Pygmy Rice Rat (Oligoryzomys costaricensis), 429. Sprightly Pygmy Rice Rat (Oligoryzomys vegetus), 430. Delicate Pygmy Rice Rat (Oligoryzomys delicatus), 431. Grayish Pygmy Rice Rat (Oligoryzomys griseolus), 432. Hairy Pygmy Rice Rat (Oligoryzomys messorius), 433. Tschudi’s Pygmy Rice Rat (Oligoryzomys destructor), 434. Sandy Pygmy Rice Rat (Oligoryzomys arenalis), 435. Andean Pygmy Rice Rat (Oligoryzomys andinus), 436. Small-eared Pygmy Rice Rat (Oligoryzomys macrotis), 437. Utiariti Pygmy Rice Rat (Oligoryzomys utiaritensis), 438. Straw-colored Pygmy Rice Rat (Oligoryzomys stramineus), 439. Mato Grosso Pygmy Rice Rat (Oligoryzomys mattogrossae), 440. Moojen’s Pygmy Rice Rat (Oligoryzomys moojeni), 441. Highlands Pygmy Rice Rat (Oligoryzomys rupestris), 442. Black-footed Pygmy Rice Rat (Oligoryzomys nigripes), 443. San Javier's Pygmy Rice Rat (Oligoryzomys brendae), 444. Chacoan Pygmy Rice Rat (Oligoryzomys chacoensts), 445. Fornes’s Pygmy Rice Rat (Oligoryzomys fornest), 446. Yellow Pygmy Rice Rat (Oligoryzomys flavescens), 447. Long-tailed Pygmy Rice Rat (Oligoryzomys longicaudatus), 448. Painted Bristly Mouse (Neacomys pictus), 449. Narrow-footed Bristly Mouse (Neacomys tenuipes), 450. Guianan Bristly Mouse (Neacomys guianae), 451. Paracou Bristly Mouse (Neacomys paracou), 452. Dubost’s Bristly Mouse (Neacomys dubosti), 453. Large Bristly Mouse (Neacomys spinosus), 454. Pleasant Bristly Mouse (Neacomys amoenus), 455. Vargas Llosa’s Bristly Mouse (Neacomys vargasllosai), 456. Minute Bristly Mouse (Neacomys minutus), 457. Musser’s Bristly Mouse (Neacomys musseri)

Distribution. From SW Para to NW Mato Grosso states, C Brazil.