Micranthes lyallii |
Micranthes gaspensis |
|
---|---|---|
Lyall's saxifrage, red-stem saxifrage |
Gaspé saxifrage, saxifrage de gaspésie |
|
Habit | Plants solitary or sometimes mat-forming, rhizomatous. | Plants solitary or tufted, from caudex. |
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 flattened, 0.7–2.5 cm; blade obtrullate or obovate to ovate, 0.8–2.5 cm, ± coriaceous, base attenuate to ± cuneate, margins serrate to dentate on distal 2/3, ciliate, surfaces tangled, reddish brown-hairy abaxially, glabrous or glabrate adaxially. |
Inflorescences | usually 10–15-flowered, lax, cylindric thyrses, (red), (4–)7–30 cm, sparsely purple-tipped stipitate-glandular. |
3–10-flowered, subcapitate to spicate cymes or thyrses, 2–10(–15) cm, glabrate to sparsely hairy proximally, ± densely purple-tipped stipitate-glandular distally. |
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 erect, reflexed in fruit, triangular to deltate; petals white, not spotted, obovate, clawed, 1.5–2 mm, ± equaling sepals; filaments linear, flattened; pistils connate to 1/2 their lengths; ovary 1/2 inferior, appearing more superior in fruit. |
Capsules | green to yellow, distal 1/2 purple, ± folliclelike, (basally connate). |
green, becoming reddish or purplish, folliclelike. |
2n | = ca. 56, 58. |
= 40. |
Micranthes lyallii |
Micranthes gaspensis |
|
Phenology | Flowering summer–early autumn. | Flowering summer. |
Habitat | Wet, rocky meadows, mountain to alpine streamsides | North- or west-facing, abrupt schist slopes, cliff bases, mossy or muddy areas, streamsides, seepages, cool ravines or chimneys |
Elevation | 800-4000 m (2600-13100 ft) | 800-1100 m (2600-3600 ft) |
Distribution |
AK; ID; MT; WA; AB; BC; NT; YT
|
QC |
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 gaspensis appears to be the stabilized hybrid derivative of M. nivalis and M. tenuis (C. Gervais et al. 1995), known only from the Shickshock Mountains of the Gaspé Peninsula; the chromosome number is intermediate between that of the parents (2n = 60 and 20, respectively), and seeds are fertile. Neither parent occurs any longer in the Gaspé Peninsula, and the plants appear to self-perpetuate. F1 hybrids of the two parent species (also 2n = 40) occur in Yukon (D. L. Krause and K. I. Beamish 1973) and possibly at other locations throughout their range of sympatry, such as northern Quebec and Labrador; such hybrids will key out with Micranthes gaspensis. Individuals called Saxifraga rufopilosa (Hultén) A. E. Porsild [S. nivalis (Linnaeus) Small var. rufopilosa Hultén] from Yukon and Alaska (W. J. Cody 2000) also will key out here. These may represent either the F1 hybrids mentioned above or stabilized hybrid populations such as those in the Gaspé. It is possible that such stabilized populations would fit under the name M. gaspensis. A systematic study is needed before a taxonomic conclusion can be reached concerning their status. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 8, p. 57. | FNA vol. 8, p. 65. |
Parent taxa | Saxifragaceae > Micranthes | Saxifragaceae > Micranthes |
Sibling taxa | ||
Synonyms | Saxifraga lyallii, Saxifraga lyallii subsp. hultenii, Saxifraga lyallii var. hultenii | Saxifraga gaspensis |
Name authority | (Engler) Small: in N. L. Britton et al., N. Amer. Fl. 22: 143. 1905 , | (Fernald) Small: in N. L. Britton et al., N. Amer. Fl. 22: 552. 1918 , |
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