Micranthes lyallii |
Micranthes tempestiva |
|
---|---|---|
Lyall's saxifrage, red-stem saxifrage |
storm saxifrage |
|
Habit | Plants solitary or sometimes mat-forming, rhizomatous. | Plants solitary or in groups, with bulbils on caudices. |
Leaves | basal; petiole rounded to flattened, 2–10 cm; blade spatulate to obovate, 0.8–8 cm, thin, base cuneate to slightly attenuate, margins serrate to dentate, eciliate or sparsely glandular-ciliate, surfaces abaxially glabrous, adaxially sparsely brown-hairy. |
basal; petiole indistinct (leaves appearing sessile), flattened, 2–8+ mm; blade oblanceolate to obovate, 4–10(–30) mm, fleshy, base cuneate to attenuate, margins entire or minutely denticulate, eciliate, (apex acute to obtuse or rounded), surfaces ± glabrous; (venation pinnate or palmate). |
Inflorescences | usually 10–15-flowered, lax, cylindric thyrses, (red), (4–)7–30 cm, sparsely purple-tipped stipitate-glandular. |
5–15(–20)-flowered, congested thyrses, 3–10(–15) cm, glabrous or sparsely purple-tipped stipitate-glandular. |
Flowers | sepals reflexed, oblong to elliptic; petals white, each with 2 basal yellowish green spots, elliptic to round, clawed, 2–5.5 mm, longer than sepals; filaments club-shaped, (to 6 mm); pistils connate 1/2+ their lengths; ovary superior, (to 1/3 adnate to hypanthium). |
sepals spreading, ovate; petals white, not spotted, linear to obovate, clawed, to 1.5 mm, shorter than sepals; filaments linear, flattened; pistils connate to 1/2 their lengths; ovary inferior. |
Capsules | green to yellow, distal 1/2 purple, ± folliclelike, (basally connate). |
reddish purple, valvate. |
2n | = ca. 56, 58. |
= 10. |
Micranthes lyallii |
Micranthes tempestiva |
|
Phenology | Flowering summer–early autumn. | Flowering summer. |
Habitat | Wet, rocky meadows, mountain to alpine streamsides | Rocky ledges, slopes, or snow-bed meadows |
Elevation | 800-4000 m (2600-13100 ft) | 2400-3200 m (7900-10500 ft) |
Distribution |
AK; ID; MT; WA; AB; BC; NT; YT
|
MT |
Discussion | Although they have nearly disjunct sets of populations, the subspecies of Micranthes lyallii are difficult to distinguish from each other. The more northern plants tend to be larger with wider leaves and often have been called Saxifraga lyallii subsp. or var. hultenii. Apparent hybrids with M. odontoloma occur in Alberta, British Columbia, and northern Idaho, and near Glacier National Park, Montana. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Micranthes tempestiva is known only from the Bitterroot Mountains and Anaconda Range. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 8, p. 57. | FNA vol. 8, p. 69. |
Parent taxa | Saxifragaceae > Micranthes | Saxifragaceae > Micranthes |
Sibling taxa | ||
Synonyms | Saxifraga lyallii, Saxifraga lyallii subsp. hultenii, Saxifraga lyallii var. hultenii | Saxifraga tempestiva |
Name authority | (Engler) Small: in N. L. Britton et al., N. Amer. Fl. 22: 143. 1905 , | (Elvander & Denton) Brouillet & Gornall: J. Bot. Res. Inst. Texas 1: 1021. 2007 , |
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