Sorexpreblei (Jackson,1922) 



Preble's Shrew 



Insectivora: Soricidae 



Global Rank: G4; State Rank: S3 



DESCRIPTION: Preble's Shrew resembles other long-tailed shrews in Montana, although it is quite small 

 (2.1-4.1 grams). The tail is bi-colored: dark above and pale below. Dorsal fur is grayish to brownish, with 

 silvery pelage on the belly. Sexes are similar in appearance. This species is virtually impossible to identify 

 using extemal criteria, however. One must examine the teeth and skull to properly distinguish this shrew 

 from other species. There are medial tines on the first upper incisors well within the pigmented portion of 

 the teeth, and the third unicuspid is larger than, or about equal in size to, the fourth unicuspid, placing this 

 shrew in the cinereus group. A series of skull measurements is necessary to differentiate S. preblei from S. 

 cinereus and S. haydeni where the species overlap. Condylobasal length is usually < 1 4.8 mm, cranial 

 breadth is usually < 7.5 mm. 



DISTRIBUTION: Preble's Shrew ranges from northeastern California, northern Nevada, northern Utah, 

 and southwestem Wyoming through eastern Oregon, southeastem Washington, central Idaho and across 

 Montana, appearing as several disjunct populations, partly a resuh of unequal sampling across the geo- 

 graphical range. In Montana Preble's Shrew has previously been confirmed in Big Hom, Dawson, Fergus, 

 Gallatin, Glacier, Judith Basin, Ravalli, Silver Bow, and Sweet Grass counties (14 total locations), and 

 reported from Carbon, Phillips, Valley, and Wheatland counties. The 1 999 records (this study) are the first 

 for the Centennial Valley and Beaverhead County. 



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