Panarctic Flora

641034 Potentilla subgorodkovii Jurtz.

• Jurtz., Bot. Zhurn. 78, 11: 83 (1993). Holotype (ALA!): Alaska: the Sheenjek River north of the junction with Old Woman Creek, 22. June 1956, leg. B. Kessel.

Geography: Amphi-Beringian: RFE ALA CAN.

Notes: Yurtsev: Potentilla subgorodkovii approaches another species of the P. uniflora aggregate - P. subvahliana - a true pulvinate calciphilous plant with long persisting whole stiff pilose leaves. From the abovementioned species our plant differs in shortly and densely tomentose petioles, under higher sparse layer of patent straight hairs, the presence of tomentum on lanceolate stipules of the cauline leaves, with less dissected blades, styles dilatate and glandulose at base, etc. The differences from other species of the aggregate are more numerous. The species proved to be relatively common in various parts of western, northern, and eastern Alaska and in two localities of Central and West Chukotka.

Yurtsev, Elven, and Murray: Potentilla subgorodkovii is assumed to be a hybrid species from P. crebridens subsp. hemicryophila and P. subvahliana and is predominantly North American (as is P. subvahliana). There are, however, indications in the northwestern North American material that other species may partake in this complex, especially P. villosula in south-central Alaska, perhaps P. vulcanicola in western and central Alaska, and perhaps P. nivea throughout. We provisionally apply the name P. subgorodkovii for this probably heterogeneous assemblage which constitutes a major part (perhaps the major part) of what previously has been assigned as P. uniflora from northwestern North America. It occurs far south in the Cordilleras and east to Pelly Lake in mainland Nunavut and to Banks and Melville islands in the archipelago.