Micranthes gaspensis |
Micranthes marshallii |
|
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Gaspé saxifrage, saxifrage de gaspésie |
Idaho saxifrage, Marshall's saxifrage |
|
Habit | Plants solitary or tufted, from caudex. | Plants in groups or sometimes mat-forming, rhizomatous. |
Leaves | 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. |
basal; petiole flattened, 3–15 cm; blade ovate, 1–5 cm, ± fleshy, base attenuate, margins shallowly crenate-serrate (teeth ca. 2 mm), eciliate, surfaces sparsely tangled, reddish brown-hairy abaxially, glabrate adaxially. |
Inflorescences | 3–10-flowered, subcapitate to spicate cymes or thyrses, 2–10(–15) cm, glabrate to sparsely hairy proximally, ± densely purple-tipped stipitate-glandular distally. |
15–50+-flowered, open, lax thyrses, 20–40 cm, purple-tipped stipitate-glandular. |
Flowers | 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. |
sepals reflexed, lanceolate to oblong; petals white, with 2 basal yellow spots (often faded when dried), ovate, clawed, 1.5–4.5 mm, longer than sepals; filaments strongly club-shaped, sometimes petaloid (short-clawed, equaling petals); pistils distinct almost to base; ovary superior, (to 1/3 adnate to hypanthium). |
Capsules | green, becoming reddish or purplish, folliclelike. |
greenish to reddish purple, folliclelike. |
2n | = 40. |
= 20. |
Micranthes gaspensis |
Micranthes marshallii |
|
Phenology | Flowering summer. | Flowering spring. |
Habitat | North- or west-facing, abrupt schist slopes, cliff bases, mossy or muddy areas, streamsides, seepages, cool ravines or chimneys | Deeply shaded watercourses, stream banks, seeps |
Elevation | 800-1100 m (2600-3600 ft) | 100-1000 m (300-3300 ft) |
Distribution |
QC |
CA; OR
|
Discussion | 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. 65. | FNA vol. 8, p. 63. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Saxifraga gaspensis | Saxifraga marshallii |
Name authority | (Fernald) Small: in N. L. Britton et al., N. Amer. Fl. 22: 552. 1918 , | (Greene) Small: in N. L. Britton et al., N. Amer. Fl. 22: 145. 1905 , |
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