500105 Micranthes foliolosa (R. Br.) Gornall
Distribution
Northern Fennoscandia: Scattered
Kanin - Pechora: Scattered
Svalbard - Franz Joseph Land: Frequent
Polar Ural - Novaya Zemlya: Frequent
Yamal - Gydan: Frequent
Taimyr - Severnaya Zemlya: Frequent
Anabar - Onenyo: Frequent
Kharaulakh: Frequent
Yana - Kolyma: Frequent
West Chukotka: Frequent
Wrangel Island: Scattered
South Chukotka: Frequent
East Chukotka: Frequent
Western Alaska: Frequent
Northern Alaska - Yukon: Frequent
Central Canada: Frequent
Hudson Bay - Labrador: Frequent
Ellesmere Island: Frequent
Western Greenland: Frequent
Eastern Greenland: Frequent
Polar desert: Scattered
Northern arctic Tundra: Frequent
Mid Arctic Tundra: Frequent
Southern Arcti Tundra: Frequent
Shrub Tundra: Frequent
Bordering boreal or alpine areas: Scattered
- Gornall, J. Bot. Res. Inst. Texas 1: 1020 (2007). - Saxifraga foliolosa R. Br., Chlor. Melvill.: 17 (1823). Holotype (BM): Canada: the Northwest Territories?, "Melville Island, Cap. Nels.", 1819-1820, leg. J. Ross. - Saxifraga stellaris var. foliolosa (R. Br.) Turcz., Pl. Imag. Descr. Fl. Russ. 7: 80 (1846). - Spatularia foliolosa (R. Br.) Small, N. Amer. Fl. 22, 2: 149 (1905).
- ?Saxifraga stellaris var. multiflora Hultén, Ark. Bot., n. s., 7, 1: 68 (1968). Holotype (S!): Alaska: the Seward Peninsula, "Bering Strait, Wales", 23. Aug. 1964, leg. E. Hultén.
2n=
(1) 40 (4x, x = 10, or 5x, x = 8). - Far East (East Chukotka). - Zhukova et al. (1973); Zhukova and Petrovsky (1987a); Devyatov et al. (1997). All three reports possibly based on the same count(s).
(2) 48 (6x, x = 8). - Far East (East Chukotka). - Zhukova and Petrovsky (1987a).
(3) 56 (7x, x = 8). - Europe (N), Russia (N), Siberia (N), Far East (N), Alaska, Canada, Greenland. - Numerous reports.
(4) 64 (8x, x = 8). - Greenland. - Harmsen (1939, embryo 2n = 64, endosperm 3n = 96).
Löve and Löve (1975a) considered this species to have a uniform chromosome number of 2n = 56 and omitted the reports of other numbers.
Geography: Circumpolar: NOR RUS SIB RFE ALA CAN GRL.
Notes: Micranthes foliolosa approaches the Arctic in Iceland but probably not close enough to be a borderline case (Kristinsson 2008).
Zhmylev: This species is probably a complex of 2-3 entities formed as a result of polyploidy of pseudoviviparous races of Micranthes stellaris, M. redofskyi, and M. ferruginea.
Elven: The realisation of pseudovivipary (bulbils) may be posterior to the polyploidization, not a feature expressed in the parental plants. Arctic plants of M. foliolosa do not vary much. All are morphologically much more similar to M. redofskyi than to M. stellaris (or M. ferruginea). A molecular investigation (AFLP, A. Tribsch unpubl.) connects M. foliolosa sampled throughout the Arctic closely to Siberian M. redofskyi. Participation of M. stellaris in an allopolyploid origin is not supported. Participation of M. ferruginea cannot be excluded.
Most populations consist of plants with bulbils only or with a single, often small or deformed apical flower. However, populations of large plants with branched scapes and multiple, well-formed flowers are frequent along the Bering Strait in both western Alaska and East Chukotka. Hultén (1968a and later) named these plants Saxifraga foliolosa var. multiflora and synonymized them with Saxifraga [Micranthes redofskyi]. Zhmylev (PAF proposal) synonymized var. multiflora with M. foliolosa. We have inspected the type and the other Hultén material (S) of var. multiflora, and also Chukotkan material, and agree with Zhmylev that this variety is not the same as M. redofskyi. Note that the lowest chromosome numbers for M. foliolosa (2n = 40, 48) are recorded in the regions where this species is most floriferous and where its range overlaps with that of M. redofskyi. Variety multiflora may be a "step" in a hybrid series between M. redofskyi and perhaps M. ferruginea on one side and M. foliolosa s. str. on the other.
Higher Taxa
- Micranthes [5001,genus]