Ranunculus austro-oreganus |
Ranunculus adoneus |
|
|---|---|---|
|
southern Oregon buttercup |
alpine buttercup |
|
| Roots | never tuberous. |
slender, 0.8-1.4 mm thick. |
| Stems | erect or ascending, never rooting nodally, crisped-pilose, base not bulbous. |
erect from large caudices, 9-25 cm, glabrous, each with 1-3 flowers. |
| Basal leaves | persistent, blades circular to reniform in outline, 2-3x-dissected into linear segments, 0.9-2.5 × 1.1-2.8 cm, base obtuse, margins entire, apices of segments narrowly rounded to acute. |
|
| Basal leaf blades | broadly rhombic to semicircular in outline, 3-parted, 2.8-4.3 × 3-5.5 cm, segments 3-lobed, ultimate segments lanceolate, margins entire or toothed, apex narrowly acute or acuminate. |
|
| Flowers | receptacle glabrous; sepals reflexed 1 mm above base, 4-6 × 1.5-3 mm, densely pilose; petals 5, abaxially red, adaxially yellow, 10-12 × 4-6 mm. |
pedicels glabrous; receptacle glabrous; sepals 4-11 × 3-7 mm, abaxially sparsely pilose, hairs colorless; petals 5-10, 8-15 × 8-19 mm; nectary scale glabrous. |
| Heads | of achenes hemispheric, 4-7 × 7-10 mm; achenes 3.4-4.2 × 2.8-3.2 mm, sometimes basally pilose, margin forming narrow rib 0.1-0.2 mm wide; beak persistent, lance-subulate, straight or somewhat curved distally, 1.6-2.6 mm. |
of achenes ovoid, 6-12 × 5-9 mm; achenes 1.8-2.4 × 1-1.4 mm, glabrous or nearly so; beak subulate, straight, 1.2-1.7 mm. |
| 2 | n = 16. |
|
Ranunculus austro-oreganus |
Ranunculus adoneus |
|
| Phenology | Flowering spring (May). | |
| Habitat | Grassy hillsides | Spring-summer (May–Sep). Alpine and subalpine meadows, usually around melting snowbanks |
| Elevation | 500 m [1600 ft] | 2500-4000 m [8200-13100 ft] |
| Distribution |
OR
|
CO; ID; MT; NV; UT; WY
|
| Discussion | Of conservation concern. Ranunculus austro-oreganus is doubtfully distinct from R. occidentalis var. howellii. L. D. Benson (1954) described the stem as bulbous-based and similar to that of R. bulbosus, but a differentiated base is not evident in material I have seen (some of which was cited by Benson). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Most collections of Ranunculus adoneus from Colorado, including the type specimen, tend to be small, with narrow leaf segments (only 0.5-1 mm wide) and large flowers. The more widespread form, with leaf segments 1-2 mm wide and more variable flowers, has been called R. adoneus var. alpinus. The leaf and flower characteristics are very poorly correlated, however, and specimens referable to var. alpinus vary greatly in stature and flower size, so the two forms scarcely merit formal recognition. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
| Parent taxa | ||
| Sibling taxa | ||
| Synonyms | R. adoneus var. alpinus, R. eschscholtzii var. adoneus, R. eschscholtzii var. alpinus | |
| Name authority | L. D. Benson: Amer. Midl. Naturalist 52: 341. (1954) | A. Gray: Proc. Acad. Nat. Sci. Philadelphia 15: 56. (1863) |
| Source | FNA vol. 3. | FNA vol. 3. |
| Web links |
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