290.

Brush Deermouse

Peromyscus boylii

French: Péromyscus de Boyle / German: Unterholz-Hirschmaus / Spanish: Ratén ciervo cepillo

Other common names: Brush Mouse

Taxonomy. Hesperomys boylii Baird, 1855, “on middle fork of the American River [near Auburn, El Dorado County], California,” USA .

Peromyscus boylii is in the boylii species group. It once contained as many twelve subspecies, but several taxonomic revisions by R. D. Bradley and colleagues in 2014 and 2017 reduced the number to four. Four subspecies recognized.

Subspecies and Distribution.

P.b.boyli:Baird,1855—NCalifornia,USA.

P.b.glasselliBurt,1932—knownonlyfromthetypelocalityonSanPedroNolascoI,Sonora,Mexico.

P.b.rowley:J.A.Allen,1893—fromSWCaliforniaEtoSColorado,WOklahoma Panhandle,andNWTexas,USA,andNWBajaCalifornia,andfromWSonora,Chihuahua,andNWCoahuilaSthroughtheMexicanAltiplanetoQuerétaroandWHidalgo,Mexico.

P.b. utahensis Durrant, 1946 — restricted to Utah, USA.

Descriptive notes. Head-body 86-95 mm, tail 89-115 mm, ear 18-21 mm, hindfoot 12-22 mm; weight 19-30 g. The Brush Deermouse is medium-sized, with diagnostically long tail relative to head-body length. Dorsum is reddish olive to brown. Sides have distinct yellow-brown or ocherous orange band that extends from rump to cheek. Venteris white to cream. Hindfeet are white, with dusky ankle instead of white in morphologically similar species such the Northern White-ankled Deermouse (FP. laceianus) or the Southern White-ankled Deermouse ( P. pectoralis). Ears are dark gray and medium in size—much smaller than in the Pinyon Deermouse (P. true). Tail is long, bicolored (brown on dorsum and white on ventrum), and strongly tufted. Because many former subspecies of P. boylii have recently been elevated to species status, chromosomal and DNA sequence are the most reliable way to distinguish it from its close relatives.

Habitat. Canyons, rocky outcroppings, and forested regions ranging from desert and xeric scrublands to pine-oak forests,typically at elevations of 914-2590 m (most commonly greater than 1500 m).

Food and Feeding. The Brush Deermouse eats a variety of seeds, acorns, berries, and arthropods.

Breeding. Given large distribution of the Brush Deermouse, breeding season varies considerably. Typically, spring and autumn pattern appears to be the most common. In many areas, reproduction seems to coincide with local mast production. Gestation is 29 days. Litters have 1-6 young.

Activity patterns. The Brush Deermouse is presumably nocturnal and probably semiarboreal.

Movements, Home range and Social organization. Densities are 2-46 ind/ha, and home ranges are 0-11-0-47 ha.

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

Bibliography. Allen (1893), Alvarez & Arroyo-Cabrales (1990), Anderson (1972), Baker & Greer (1962), Bradley, Carroll et al. (2004), Bradley, Ordénez-Garza, Ceballos et al. (2017), Bradley, Ordénez-Garza, Sotero-Caio et al. (2014), Espinosa & Chavez (2014), Hoffmeister (1986), Houseal et al. (1987), Kalcounis-Ruppell & Millar (2002), Kalcounis-Ruppell & Spoon (2009), Long (1940), Miller (1893), Musser & Carleton (2005), Osgood (1909), Schmidly et al. (1988), Storer et al. (1944), Tiemann-Boege et al. (2000).