Panarctic Flora

630515 Astragalus richardsonii E. Sheld.

2n= 48 (6x). - Ledingham and Rever (1963).
Not included: A report of 2n = 32 (4x) from Churchill at Hudson Bay in Manitoba (Löve and Löve 1982b), far outside its accepted geographical range.

Geography: North American (NW): ALA CAN.

Notes: Murray and Elven: Astragalus richardsonii is the species about which our opinions differ most. Yurtsev's opinion was that the arctic plants in northwestern Canada belong within A. tolmaczevii. He probably did not see any of the more recent northern Alaskan collections (ALA) that now geographically connect the Canadian and Asian parts of his proposed range. He was of the opinion that the type of A. richardsonii differs from the arctic plants and belongs in A. aboriginorum. He stated that the real A. richardsonii shares all features of boreal steppe (prairie) A. aboriginorum.

We agree that the arctic plants are clearly different from A. aboriginorum but do not agree that they should be included in A. tolmaczevii. We find consistent differences from the northern Yakutian plants we have studied of that species. We disagree with the rejection of the name A. richardsonii for the northwestern Canadian (and northern Alaskan) plants. Yurtsev stated that he based his conclusion on the type but as far as we know a type for A. richardsonii has not yet been designated (see above). As Canadian authors see it, A. richardsonii is a northwestern Canadian plant with a range from the northern forest belt from Great Bear Lake and the Mackenzie River into the Arctic east to Bathurst Inlet and north to Banks and Victoria islands. The survey of material in ALA convinced us that also a significant amount of northeastern Alaskan material should be included in this species. It is fairly common along the Arctic Coast and in the northeastern parts of the Brooks Range and the Philip Smith Mountains. The possible type of A. richardsonii (see Gillett et al. 2007) is from the southern part of the range but it is premature to neglect this name and to replace it with the nearly 100 years younger name A. tolmaczevii. We keep the option open that the Wrangel Island plant belongs together with the northwestern North American ones, but then as different from the A. tolmaczevii of Taimyr and Yakutia.