Micranthes howellii |
Micranthes rhomboidea |
|
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Howell's saxifrage |
diamond-leaf saxifrage |
|
Habit | Plants solitary or in groups, with bulbils on caudices. | Plants solitary or tufted, with bulbils on caudices. |
Leaves | basal; petiole flattened, 1–4 cm; blade oblong to narrowly ovate, 1–2(–3) cm, ± fleshy, base attenuate, margins sharply serrate, eciliate, surfaces sparsely tangled, reddish brown-hairy abaxially, glabrous adaxially. |
basal; petiole flattened, 1–3 cm; blade broadly ovate to triangular, 1–3 cm, fleshy, base attenuate, margins coarsely serrate, ciliate, surfaces sparsely to moderately tangled, reddish brown-hairy abaxially, glabrous adaxially. |
Inflorescences | 5–10(–20)-flowered, very open, lax, ± flat-topped cymes or thyrses, 5–10(–20) cm, glabrate to sparsely purple-tipped stipitate-glandular; (bracts glabrous). |
(5–)10–40-flowered, congested, ± glomerate or capitate thyrses, 4–20 cm, usually densely yellow- to cream-tipped stipitate-glandular. |
Flowers | sepals strongly reflexed, elliptic, (surfaces glabrous); petals white, not spotted, obovate to elliptic, clawed, 2.5–4.5 mm, longer than sepals; filaments linear, flattened; pistils distinct almost to base; ovary ± superior. |
sepals ascending, ovate; petals white, not spotted, oblong to elliptic, clawed, 2–4 mm, 1.5+ times as long as sepals; filaments linear, flattened; pistils connate to 1/2 their lengths; ovary inferior, appearing more superior in fruit. |
Capsules | purple, valvate. |
purple, folliclelike. |
2n | = 20, 38, 40, 56. |
|
Micranthes howellii |
Micranthes rhomboidea |
|
Phenology | Flowering early spring–early summer. | Flowering late spring–summer. |
Habitat | Wet, rocky ledges and crevices | Subalpine and alpine meadows |
Elevation | 0-900 m (0-3000 ft) | 1500-4600 m (4900-15100 ft) |
Distribution |
CA; OR
|
AZ; CO; ID; MT; NM; UT; WY
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Discussion | Micranthes rhomboidea is somewhat polymorphic; variants have been given taxonomic designations with little consistency. The chromosome number variation needs thorough study, as in other species of Micranthes, because no obvious correlations with morphology or geographic distribution are known (B. L. Bethers 1973). Reports from Canada (Alberta, Saskatchewan) were rejected as misidentifications of M. occidentalis. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 8, p. 63. | FNA vol. 8, p. 69. |
Parent taxa | Saxifragaceae > Micranthes | Saxifragaceae > Micranthes |
Sibling taxa | ||
Synonyms | Saxifraga howellii | Saxifraga rhomboidea, Saxifraga austrina, Saxifraga rhomboidea var. austrina, Saxifraga rhomboidea var. franciscana |
Name authority | (Greene) Small: in N. L. Britton et al., N. Amer. Fl. 22: 140. (1905) | (Greene) Small: in N. L. Britton et al., N. Amer. Fl. 22: 136. 1905 , |
Web links |