Micranthes gaspensis |
Micranthes careyana |
|
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Gaspé saxifrage, saxifrage de gaspésie |
Carey's saxifrage |
|
Habit | Plants solitary or tufted, from caudex. | Plants often mat-forming, with extensive rhizomes. |
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, 1–7 cm; blade rounded or broadly ovate to oblong, 1–7 cm, thin, base truncate, margins coarsely serrate to dentate, sparsely ciliate, surfaces sparsely to ± densely tangled, reddish brown-hairy. |
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. |
40+-flowered, lax, open thyrses, 10–40(–50) 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 spreading, broadly ovate; petals white, sometimes some with 2 faint, basal yellow spots (sometimes fading upon drying), narrowly ovate to elliptic, clawed, 2–4(–5) mm, 2+ times as long as sepals; filaments linear, flattened; pistils distinct almost to base; ovary superior, (to 1/3 adnate to hypanthium). |
Capsules | green, becoming reddish or purplish, folliclelike. |
green, ± purple tinged, folliclelike. |
2n | = 40. |
|
Micranthes gaspensis |
Micranthes careyana |
|
Phenology | Flowering summer. | Flowering spring–early summer. |
Habitat | North- or west-facing, abrupt schist slopes, cliff bases, mossy or muddy areas, streamsides, seepages, cool ravines or chimneys | Moist soil at bases of vertical or overhanging rock outcrops, seeps |
Elevation | 800-1100 m (2600-3600 ft) | 500-1600 m (1600-5200 ft) |
Distribution |
QC |
AL; GA; KY; NC; TN; VA; WV |
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.) |
Micranthes careyana is very similar to M. caroliniana; both are in need of study. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 8, p. 65. | FNA vol. 8, p. 61. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Saxifraga gaspensis | Saxifraga careyana, Saxifraga tennesseensis |
Name authority | (Fernald) Small: in N. L. Britton et al., N. Amer. Fl. 22: 552. 1918 , | (A. Gray) Small: Fl. S.E. U.S., 501. 1903 , |
Web links |