Micranthes nelsoniana |
Micranthes nivalis |
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dotted saxifrage, heartleaf saxifrage, Nelson's saxifrage, saxifrage |
alpine saxifrage, saxifrage des neiges, snow saxifrage |
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Habit | Plants solitary or tufted, with bulbils on branched caudices, rhizomatous. | Plants tufted, with bulbils on caudices. | ||||||||||||||||
Leaves | basal; petiole rounded, 3–30 cm; blade reniform to round, 2–9 cm, thin or slightly fleshy, sometimes thick and fleshy, base cordate, margins deeply crenate, eciliate or sparsely short glandular-ciliate, surfaces glabrous or ± hairy. |
basal; petiole flattened, (0.4–)1–4 cm; blade ovate to ± round, sometimes elliptic or oblong, (0.5–)1–4 cm, thick, coriaceous, base attenuate to ± truncate, margins serrate to dentate on distal 2/3 (sometimes more), proximally ciliate, surfaces ± densely tangled, reddish brown-hairy abaxially, glabrous or glabrate adaxially. |
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Inflorescences | 10+-flowered, ± open, lax to congested, conic, sometimes also glomerate thyrses, 10–35 cm, tangled-hairy (pilose-arachnoid) at least distally, sometimes also purple- or brown-tipped stipitate-glandular. |
(5–)10–40-flowered, congested, almost capitate thyrses, (3–)7–20 cm, ± densely purple-tipped stipitate-glandular. |
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Flowers | sepals reflexed, ± ovate; petals white to pinkish, rarely orange-spotted, ovate to oblong, narrowly to broadly clawed, 2.5–4.5 mm, longer than sepals; filaments distinctly club-shaped; pistils connate 1/2–3/4 their lengths; ovary superior (to 1/3 adnate to hypanthium). |
sepals erect, spreading in fruit, ovate to deltate; petals white, sometimes pink tinged, not spotted, oblong to ovate, clawed, 2–4 mm, ± equaling sepals; filaments linear, flattened; pistils connate ca. 1/2 their lengths; ovary 1/2 inferior, appearing more superior in fruit. |
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Capsules | green to yellow and purplish tinged to dark purple, valvate. |
green, becoming reddish to purplish, folliclelike. |
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2n | = 60. |
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Micranthes nelsoniana |
Micranthes nivalis |
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Phenology | Flowering summer. | |||||||||||||||||
Habitat | Open, mossy tundra, rocky ridges, or shady ledges | |||||||||||||||||
Elevation | 0-1500 m (0-4900 ft) | |||||||||||||||||
Distribution |
AK; OR; WA; AB; BC; NT; NU; YT; Europe (ne Russia); Asia
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AK; AB; BC; LB; NT; NU; QC; YT; Greenland; Europe; Asia (Himalayas, Kamchatka, Siberia) |
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Discussion | Varieties 6 (5 in the flora). Although sometimes reported for North America, Saxifraga nelsoniana var. aestivalis (Fischer & C. A. Meyer) H. Ohba (S. aestivalis Fischer & C. A. Meyer) is found only in Eurasia. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Micranthes nivalis is closely related to M. tenuis. All records of M. nivalis in the United States (except Alaska) appear to be misapplied to or misidentifications of M. aprica, M. occidentalis, or M. rhomboidea. Occasional, dwarfed specimens of M. hieraciifolia and M. subapetala are similarly mislabelled. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 8, p. 54. | FNA vol. 8, p. 64. | ||||||||||||||||
Parent taxa | Saxifragaceae > Micranthes | Saxifragaceae > Micranthes | ||||||||||||||||
Sibling taxa | ||||||||||||||||||
Subordinate taxa | ||||||||||||||||||
Synonyms | Saxifraga nelsoniana, Saxifraga punctata subsp. nelsoniana, Saxifraga punctata var. nelsoniana | Saxifraga nivalis | ||||||||||||||||
Name authority | (D. Don) Small: in N. L. Britton et al., N. Amer. Fl. 22: 147. 1905 , | (Linnaeus) Small: in N. L. Britton et al., N. Amer. Fl. 22: 136. 1905 , | ||||||||||||||||
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