Peromyscus difficilis (J. A. Allen, 1891)

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 : 396

309.

Southern Rock Deermouse

Peromyscus difficilis

French: Péromyscus des rochers / German: Sidliche Felsen-Hirschmaus / Spanish: Raton ciervo de roca meridional

Other common names: Zacatecan Deermouse

Taxonomy. Vesperimus difficilis J. A. Allen, 1891 , Sierra de Valparaiso, Zacatecus, Mexico.

Peromyscus difficilis is in the true: species group. Its taxonomy was revised in 1961 and 1976. More recent biochemical, karyotypic, and DNA sequence data indicate that griseus , nasutus , and penicillatus forms should be assigned to P. nasutus . Five subspecies recognized.

Subspecies and Distribution.

P.d.difficilisJ.A.Allen,1891—fromSWChihuahuaSEtoGuanajuatoandN&WQuerétaro,Mexico.

P.d.amplusOsgood,1904—SHidalgo,extremeWVeracruz,NMéxico,Puebla,andNWOaxaca,Mexico.

P.d.felipensisMerriam,1898—C&SMéxico,DistritoFederal,extremeWPuebla,andCOaxaca,Mexico.

P.d.petricolaHoffmeister&delaTorre,1959—extremeSECoahuila,SNuevoLeon,NEZacatecas,NSanLuisPotosi,andextremeSWTamaulipas,Mexico.

P. d. saxicola Hoffmeister & de la Torre, 1959 — restricted to E Querétaro and N Hidalgo, Mexico.

Descriptive notes. Head-body 88-105 mm,tail 91-145 mm, ear 17-28 mm, hindfoot 22-28 mm; weight 24-32 g. The Southern Rock Deermouse is medium-sized, with grayish brown, yellowish brown, or brownish ocherous dorsum. Sides are yellowish, with distinct lateral line. Venteris whitish, suffused with gray or silver underfur; some subspecies have ocherous pectoral spot. Tail is bicolored and generally as long as or longer than head-body length. Ears are relatively large. Hindfeet are whitish. The Southern Rock Deermouse can be distinguished from the Perote Deermouse ( P. bullatus ) and the Northern Rock Deermouse ( P. nasutus ) byits larger body size and longer occipitalnasal length.

Habitat. Rocky areas in pine-oak forests and high-elevation desert scrublands and grasslands at elevations of 1200-3700 m.

Food and Feeding. The Southern Rock Deermouse mainly eats seeds but also plant stems and roots.

Breeding. Reproduction occurs in June-November. Litters have 2-3 young.

Activity patterns. The Southern Rock Deermouse is presumably nocturnal. It is usually associated with rock crevices and tree stumps, trunks, and cavities, where nests are constructed.

Movements, Home range and Social organization. Densities are 27-584 ind/ha.

Status and Conservation. Classified as Least Concern on The IUCN Red List.

Bibliography. Carleton (1989), Chavez & Ceballos (2014), Ceballos & Galindo (1984), Diersing (1976), Durish et al. (2004), Fernandez et al. (2010), Hall (1981), Hernandez-Chavez (1990), Hoffmeister & de la Torre (1961), Musser & Carleton (2005), Zimmerman, Hart & Kilpatrick (1975), Zimmerman, Kilpatrick & Hart (1978).

Figures

284. Blackish Deermouse (Peromyscus furvus), 285. Wide-rostrum Deermouse (Peromyscus latirostris), 286. Michoacan Deermouse (Peromyscus sagax), 287. Tres Marias Deermouse (Peromyscus madrenss), 288. San Esteban Deermouse (Peromyscus stephani), 289. Sinaloan Deermouse (Peromyscus simulus), 290. Brush Deermouse (Peromyscus boylu), 291. Durango Deermouse (Peromyscus schmidly), 292. Nimble-footed Deermouse (Peromyscus levipes), 293. Carleton’s Deermouse (Peromyscus carletoni), 294. Kilpatrick's Deermouse (Peromyscus kilpatricki), 295. Orizaba Deermouse (Peromyscus beatae), 296. Gleaning Deermouse (Peromyscus spicilegus), 297. Coalcoman Deermouse (Peromyscus winkelmanni), 298. Oaxacan Deermouse (Peromyscus oaxacensis), 299. Transvolcanic Deermouse (Peromyscus hylocetes), 300. Aztec Deermouse (Peromyscus aztecus), 301. Northern White-ankled Deermouse (Peromyscus laceianus), 302. Southern White-ankled Deermouse (Peromyscus pectoralis), 303. Saxicoline Deermouse (Peromyscus gratus), 304. El Carrizo Deermouse (Peromyscus ochraventer), 305. Chihuahuan Deermouse (Peromyscus polius), 306. Pinyon Deermouse (Peromyscus true), 307. Texas Deermouse (Peromyscus attwateri), 308. Northern Rock Deermouse (Peromyscus nasutus), 309. Southern Rock Deermouse (Peromyscus difficilis), 310. Perote Deermouse (Peromyscus bullatus), 312. Oaxacan Big-toothed Deermouse (Megadontomys cryophilus), 313. Nelson's Big-toothed Deermouse (Megadontomys nelsoni), 314. Xico Deermouse (Habromys simulatus), 315. Delicate Deermouse (Habromys delicatulus), 316. Schmidly’s Deermouse (Habromys schmidlyi), 317. Ixtlan Deermouse (Habromys ixtlani), 318. Chinanteco Deermouse (Habromys chinanteco), 319. Zempoaltepec Deermouse (Habromys lepturus), 320. Crested-tailed Deermouse (Habromys lophurus)

Subspecies and Distribution. P.d.difficilisJ.A.Allen,1891—fromSWChihuahuaSEtoGuanajuatoandN&WQuerétaro,Mexico. P.d.amplusOsgood,1904—SHidalgo,extremeWVeracruz,NMéxico,Puebla,andNWOaxaca,Mexico. P.d.felipensisMerriam,1898—C&SMéxico,DistritoFederal,extremeWPuebla,andCOaxaca,Mexico. P.d.petricolaHoffmeister&delaTorre,1959—extremeSECoahuila,SNuevoLeon,NEZacatecas,NSanLuisPotosi,andextremeSWTamaulipas,Mexico. P. d. saxicola Hoffmeister & de la Torre, 1959 — restricted to E Querétaro and N Hidalgo, Mexico.