Sorex portenkoi Stroganov, 1956 . Proc. Inst. Biol. W. Siberian Branch Acad. Sci. USSR, Zool., 1:11 -14.

TYPE LOCALITY: Russia, Koryaksk. Auv. Okr. "bliz pos Anadyr', poberejhe Anadyrsk limana [near Anadyr' settlement, shore of Anadyr' estuary]."

DISTRIBUTION: NE Siberia.

COMMENTS: Subgenus Otisorex . Originally described as a subspecies of cinereus and treated as such by Yudin (1972) and Okhotina (1977), then included in ugyunak (Ivanitskaya and Kozlovskii, 1985), but recently recognized as a distinct species by Zaitsev (1988), and van Zyli de Jong (1991b), who, however, pointed out its close relationship to jacksoni and ugyunak .