Sorex jacksoni Hall and Gilmore, 1932. Univ. California Pubi. Zool., 38:392.
TYPE LOCALITY: USA, "Sevoonga, 2 miles east of North Cape, St. Lawrence Island, Bering Sea, Alaska."
DISTRIBUTION: Known only from St. Lawrence Isl (Bering Sea).
COMMENTS: Subgenus Otisorex. Placed in the arcticus species group by Hall and Gilmore (1932) and in the cinereus species group by Hoffmann and Peterson (1967). Separated from cinereus by Junge and Hoffmann (1981). Van Zyll de Jong (1982) included leucogaster (= beringianus), portenkoi, and ugyunak in this species, but van Zyll de Jong (1991 b) retained all three as distinct.