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alpine saxifrage, Tolmie's alpine saxifrage, Tolmie's saxifrage

Yellowstone saxifrage

Habit Plants mat-forming, (stems trailing, thin, basally slightly woody), with slender, woody caudices. Plants solitary or in clumps, with bulbils on caudices.
Leaves

cauline, proximally crowded;

petiole absent;

blade elliptic-obovate, 0.8–1.5 cm, fleshy, base cuneate, margins entire, sometimes proximally sparsely long-ciliate, surfaces glabrous.

basal;

petiole usually indistinct, flattened, ca. 2 cm;

blade ovate or elliptic to oblanceolate, 3–15 cm, fleshy, base cuneate, margins entire or minutely denticulate, ciliate, surfaces hairy.

Inflorescences

2–10-flowered, lax cymes, sometimes solitary flowers, 3–12 cm, glabrous or purplish- or pink-tipped stipitate-glandular; (bracts 1–3, proximal).

30+-flowered, ± constricted (spikelike) to ± open thyrses, 20–75 cm, yellow- to pink- (rarely purplish-) tipped stipitate-glandular.

Flowers

sepals erect to spreading, ovate;

petals white, not spotted, linear to oblanceolate, 2.5–5 mm, longer than sepals, short- or not clawed;

filaments broadly club-shaped (± petaloid);

pistils connate to 1/2 their lengths;

ovary ± superior (to 1/4 adnate to hypanthium).

sepals reflexed, ovate;

petals absent, sometimes 1–5, pink to purplish, not spotted, elliptic, clawed, 1–2 mm, shorter than sepals;

filaments linear, flattened;

pistils connate to 1/2 their lengths;

ovary inferior.

Capsules

green, purple mottled, valvate.

dark purple, valvate.

2n

= 30.

= 76.

Micranthes tolmiei

Micranthes subapetala

Phenology Flowering summer. Flowering summer.
Habitat Arctic and alpine tundra, fell-fields Subalpine and alpine meadows, wet banks, ledges
Elevation 500-4000 m (1600-13100 ft) 1200-3000 m (3900-9800 ft)
Distribution
from FNA
AK; CA; ID; MT; NV; OR; UT; WA; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
ID; MT; WY
[WildflowerSearch map]
[BONAP county map]
Discussion

Unlike those of most Micranthes species, the leaves of M. tolmiei are proximally cauline and the ovules have two integuments. The seeds have a loose, winglike testa.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Although the species is usually distinctive, some populations of Micranthes subapetala in northern Wyoming appear more similar to M. hieraciifolia than to typical M. subapetala and may need to be re-evaluated. The distributional disjunction between the two taxa is about 1600 kilometers.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 8, p. 54. FNA vol. 8, p. 66.
Parent taxa Saxifragaceae > Micranthes Saxifragaceae > Micranthes
Sibling taxa
M. apetala, M. aprica, M. bryophora, M. californica, M. calycina, M. careyana, M. caroliniana, M. eriophora, M. ferruginea, M. foliolosa, M. fragosa, M. gaspensis, M. gormanii, M. hieraciifolia, M. hitchcockiana, M. howellii, M. idahoensis, M. integrifolia, M. lyallii, M. marshallii, M. micranthidifolia, M. nelsoniana, M. nidifica, M. nivalis, M. nudicaulis, M. occidentalis, M. odontoloma, M. oregana, M. palmeri, M. pensylvanica, M. petiolaris, M. razshivinii, M. reflexa, M. rhomboidea, M. rufidula, M. spicata, M. stellaris, M. subapetala, M. tempestiva, M. tenuis, M. texana, M. tischii, M. unalaschcensis, M. virginiensis
M. apetala, M. aprica, M. bryophora, M. californica, M. calycina, M. careyana, M. caroliniana, M. eriophora, M. ferruginea, M. foliolosa, M. fragosa, M. gaspensis, M. gormanii, M. hieraciifolia, M. hitchcockiana, M. howellii, M. idahoensis, M. integrifolia, M. lyallii, M. marshallii, M. micranthidifolia, M. nelsoniana, M. nidifica, M. nivalis, M. nudicaulis, M. occidentalis, M. odontoloma, M. oregana, M. palmeri, M. pensylvanica, M. petiolaris, M. razshivinii, M. reflexa, M. rhomboidea, M. rufidula, M. spicata, M. stellaris, M. tempestiva, M. tenuis, M. texana, M. tischii, M. tolmiei, M. unalaschcensis, M. virginiensis
Synonyms Saxifraga tolmiei, Saxifraga tolmiei var. ledifolia Saxifraga subapetala, Saxifraga oregana var. subapetala, Saxifraga rydbergii
Name authority (Torrey & A. Gray) Brouillet & Gornall: J. Bot. Res. Inst. Texas 1: 1022. 2007 , (E. E. Nelson) Small: in N. L. Britton et al., N. Amer. Fl. 22: 139. 1905 ,
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