Micranthes virginiensis |
Micranthes razshivinii |
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early saxifrage, early small-flower-saxifrage, saxifrage de virginie, Virginia saxifrage |
large-petal saxifrage, razshivin's saxifrage |
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Habit | Plants solitary or in clumps, with bulbils on caudices. | Plants solitary or in clusters, rhizomatous. |
Leaves | basal; petiole flattened, 1–9 cm; blade ovate to elliptic, 2–8 cm, ± fleshy, base attenuate, margins irregularly crenate to serrate, ciliate, surfaces sparsely to ± densely stipitate-glandular and tangled, reddish brown-hairy, adaxially glabrescent. |
basal; petiole ± distinct to indistinct, flattened, (0.3–)0.5–3 cm; blade oblanceolate to narrowly oblanceolate or narrowly spatulate, sometimes ± narrowly obovate, (0.5–)0.9–3.5 cm, ± fleshy, base ± attenuate to cuneate, margins (3–)5–7(–9)-toothed in distal 1/2 (teeth 0.5 mm), sparsely ciliate, surfaces glabrous. |
Inflorescences | 30+-flowered, (flowers sometimes secund), very open, lax, ± flat-topped thyrses, 6–50 cm, proximally hairy, distally densely purple-tipped stipitate-glandular. |
(2–)4–16-flowered, open, racemiform, sometimes paniculiform thyrses, sometimes solitary flowers, 3–15.5(–17 in fruit) cm, glabrous; (bracts reduced). |
Flowers | sepals erect to ascending (even in fruit), ovate to triangular; petals white, not spotted, broadly oblong to elliptic, not or rarely slightly clawed, 3–6 mm, 2+ times as long as sepals; filaments linear, flattened; pistils distinct almost to base; ovary ± superior, (to 1/3 adnate hypanthium). |
sepals reflexed, oblong or lanceolate to ovate; petals white to cream, often purplish, not spotted, linear to ± narrowly elliptic, not clawed, 2–4 mm, usually longer to sometimes shorter than sepals; filaments linear, flattened; pistils connate 1/2+ their lengths, (conic); ovary ± 1/2 inferior. |
Capsules | green to purplish, folliclelike. |
dark purple-black, valvate. |
2n | = 20 (+ 0–6 supernumeraries), 38. |
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Micranthes virginiensis |
Micranthes razshivinii |
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Phenology | Flowering spring. | Flowering summer. |
Habitat | Rocky hillsides, cliffs and shaded rock outcrops, stream banks, wooded slopes | Tundra, stream banks, alpine rocky slopes |
Elevation | 0-1500 m (0-4900 ft) | 400-2000 m (1300-6600 ft) |
Distribution |
AL; AR; CT; DC; GA; IL; IN; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NH; NJ; NY; OH; PA; RI; SC; TN; VA; VT; WV; MB; NB; ON; QC
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AK; NT; YT |
Discussion | Also reported for Micranthes virginiensis is 2n = 28; D. E. Soltis (1983) documented zero to six supernumerary chromosomes in this species and speculated that this report may have included eight supernumeraries. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Micranthes razshivinii is found in eastern Alaska (eastern Brooks Range, from Atigun Pass eastward and from Mount McKinley National Park eastward) into Yukon and in the Mackenzie and Richardson mountains in the Northwest Territories. Its leaves are generally narrower than those of M. calycina and the teeth are less numerous. The glabrous inflorescence branches of M. razshivinii readily distinguish it from M. calycina, which has hairy branches. The ranges of the two species may overlap or at least abut in the Atigun Pass area of the Brooks Range, in the Mount McKinley National Park area, and possibly in the Saint Elias Mountains. Hybrids would be very difficult to distinguish from the parents but may occur. They have not been observed in the material examined. Plants of this species sometimes have been misidentified as M. davurica (Willdenow) Small, a species restricted to eastern Siberia. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 8, p. 61. | FNA vol. 8, p. 59. |
Parent taxa | Saxifragaceae > Micranthes | Saxifragaceae > Micranthes |
Sibling taxa | ||
Synonyms | Saxifraga virginiensis | Saxifraga razshivinii |
Name authority | (Michaux) Small: Fl. S.E. U.S., 501. 1903 , | (Zhmylev) Brouillet & Gornall: J. Bot. Res. Inst. Texas 1: 1021. (2007) |
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