Ochrotomys Osgood 1909

Wilson, Don E. & Reeder, DeeAnn, 2005, Order Rodentia - Family Cricetidae, Mammal Species of the World: a Taxonomic and Geographic Reference (3 rd Edition), Volume 2, Baltimore: The Johns Hopkins University Press, pp. 955-1189 : 1060

Ochrotomys Osgood 1909

Ochrotomys Osgood 1909 , N. Amer. Fauna, 28: 222.

Type Species: Arvicola nuttalli Harlan 1832

Species and subspecies: 1 species:

Species Ochrotomys nuttalli (Harlan 1832)

Discussion: Ochrotomyini new tribe. Type genus— Ochrotomys Osgood, 1909 . Definition—medium-sized semiarboreal muroid rodents with tail about equal to head-and-body ( Packard, 1969); hindfoot short and broad, digit V nearly as long as II-IV, plantar pads large and close set; carotid circulation complete (character state 0 per Carleton, 1980); skull with amphoral interorbit and smooth braincase; zygomatic plate narrow, no formation of dorsal notch; tegmen tympani adnate to squamosal (Voss, 1993), alisphenoid strut present; molars more brachyodont than Peromyscus , enamel thick, accessory lophs(ids) well developed ( Hooper, 1957); m3 slightly smaller than m2, enteroconid and posterolophid usually discrete elements; vertebral column with 13 thoracic and 6 lumbar vertebrae, 1 st rib articulating 7 th cervical and 1 st thoracic ( Carleton, 1980); humerus lacking entepicondylar foramen ( Manville, 1961); three complete and four incomplete transverse palatal ridges ( Carleton, 1980); gastric glandular epithelium somewhat reduced and incisura angularis moderately deep ( Carleton, 1973), gall bladder absent ( Carleton, 1980); preputial glands large, ampullary glands absent ( Arata, 1964); baculum and phallus short and wide, spination pronounced, urethral process present, dorsal and ventral lappets lacking ( Blair, 1942; Hooper, 1958); 2n=52, G-banding patterns highly derived ( Engstrom and Bickham, 1982; Patton and Hsu, 1967). Contents— Ochrotomys Osgood, 1909 .

Although named as a subgenus of Peromyscus , the distant kinship and generic segregation of Ochrotomys have been repeatedly sustained ( Blair, 1942; Carleton, 1980; Hooper, 1958; Hooper and Musser, 1964 b; Patton and Hsu, 1967). Informally grouped with "peromyscines" by Carleton (1980), but his own results (see Carleton, 1989:115), together with karyological and molecular studies ( Engel et al., 1998; Engstrom and Bickham, 1982), suggest earlier origination within the neotomine radiation .