Potentilla concinna var. proxima

(Rydberg) S. L. Welsh & B. C. Johnston

Great Basin Naturalist 42: 25. 1982.

Conservation concernEndemicIllustrated
Basionym: Potentilla proxima Rydberg in N. L. Britton et al., N. Amer. Fl. 22: 339. 1908
Synonyms: P. beanii Clokey P. diversifolia var. proxima (Rydberg) Soják
Treatment appears in FNA Volume 9. Treatment on page 179. Mentioned on page 170, 178.

Stems (0.2–)0.6–1.6 dm, lengths 2–3(–4) times basal leaves. Basal leaves usually palmate to subpalmate, sometimes subpinnate; leaflets on tip or to distal 1/4 of leaf axis, ± overlapping, proximal pairs sometimes doubled often separated from others by 1–5(–10) mm of leaf axis; distal 1/3–2/3 of central leaflets incised 1/4–1/2 to midvein, teeth 2–4 per side, 1–3(–5) mm. Inflorescences (1–)3–12-flowered. Petals (2.5–)4–6 mm. Achenes 1.5–2 mm.


Phenology: Flowering mid summer.
Habitat: Alpine tundra, windswept ridges, stony meadows
Elevation: 2600–3900 m

Distribution

V9 261-distribution-map.jpg

Ariz., Calif., Colo., Nev., N.Mex., Utah.

Discussion

Of conservation concern.

Variety proxima is the primary phase of Potentilla concinna in the mountains of southwestern Colorado, Nevada, and Utah. Some alpine collections from New Mexico are referable to var. proxima, and isolated populations also occur in the San Francisco Peaks of Arizona (at higher elevations than otherwise sympatric var. concinna) and the White Mountains of California. Specimens from Montana keying here are provisionally placed in P. macounii.

The most distinctive feature of var. proxima is the elongate flowering stems, which are usually over twice as long as the leaves. Leaves tend to be more sparsely cottony and less bicolored than in the typical variety, the central leaflet is more often petiolulate, and flowers are commonly somewhat smaller. Collections from southwestern Utah and adjacent Nevada, including the type of Potentilla proxima, commonly have subpalmate leaves; elsewhere leaves are rarely or scarcely subpalmate.

Selected References

None.

Lower Taxa

None.
Barbara Ertter +
(Rydberg) S. L. Welsh & B. C. Johnston +
Potentilla proxima +
Ariz. +, Calif. +, Colo. +, Nev. +, N.Mex. +  and Utah. +
2600–3900 m +
Alpine tundra, windswept ridges, stony meadows +
Flowering mid summer. +
Great Basin Naturalist +
Conservation concern +, Endemic +  and Illustrated +
P. beanii +  and P. diversifolia var. proxima +
Potentilla concinna var. proxima +
Potentilla concinna +
variety +