| Betula nana subsp. exilis (Sukaczev) Hultén | |
| Publ. & Syn. | Basionym: Betula tundrarum Perfil., Bot. Zhurn. 48: 1139 (1963). Holotype (LE): European Russia: Novaya Zemlya, "prope promontorium Kankrinii, ad lit. maris Carici", 26. Aug. 1923, leg. A. Tolmachev 112. - Betula nana subsp. tundrarum (Perfil.) Á. Löve & D. Löve, Bot. Not. 128: 505 (1976). |
| Notes | Vassiljev (1966) described Betula perfiljevii as a strictly Beringian species (from Kolyma and Kamtchatka east to south-central Alaska) enclosed within the larger range of B. nana subsp. exilis. We include it fully in that subspecies. |
| Chromosomes | 28 30? (2x). - Siberia (N), Far East (N), Alaska, Canada. - Several reports. Not included: Reports of 2n = 42 from northwestern Alaska (Johnson and Packer 1968) and West Chukotka (Zhukova and Petrovsky 1975). Both are probably based on some hybrids. However, the count of Zhukova and Petrovsky was made on "the same voucher" as a 2n = 28 count. |
| Geography | Asian (NE) - amphi-Beringian - North American (N): SIB RFE ALA CAN. |
| Distribution | N = F AN = f AO = f C = R D = S E = F CC = s HL = r CE = f CS = r YK = s AW = f Kh = f CW = f Tm = r [ key ] |
| Parent taxon | Betula nana L. |
| PAF ID | 610212c |