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Photo is of parent taxon

dotted saxifrage

dotted saxifrage, heartleaf saxifrage, Nelson's saxifrage, saxifrage

Habit Plants solitary or tufted, with bulbils on branched caudices, rhizomatous.
Leaves

blades thin, not fleshy, margins 12–18-toothed.

basal;

petiole rounded, 3–30 cm;

blade reniform to round, 2–9 cm, thin or slightly fleshy, sometimes thick and fleshy, base cordate, margins deeply crenate, eciliate or sparsely short glandular-ciliate, surfaces glabrous or ± hairy.

Inflorescences

congested, tangled-ascending hairy.

10+-flowered, ± open, lax to congested, conic, sometimes also glomerate thyrses, 10–35 cm, tangled-hairy (pilose-arachnoid) at least distally, sometimes also purple- or brown-tipped stipitate-glandular.

Flowers

sepals reflexed, ± ovate;

petals white to pinkish, rarely orange-spotted, ovate to oblong, narrowly to broadly clawed, 2.5–4.5 mm, longer than sepals;

filaments distinctly club-shaped;

pistils connate 1/2–3/4 their lengths;

ovary superior (to 1/3 adnate to hypanthium).

Pistils

connate to 3/4 their lengths.

Capsules

3–8 mm.

green to yellow and purplish tinged to dark purple, valvate.

2n

= 28.

Micranthes nelsoniana var. porsildiana

Micranthes nelsoniana

Phenology Flowering summer.
Habitat Stream banks, wet areas
Elevation 0-2500 m (0-8200 ft)
Distribution
from FNA
AK; AB; BC; NT; NU; YT
from FNA
AK; OR; WA; AB; BC; NT; NU; YT; Europe (ne Russia); Asia
[WildflowerSearch map]
[BONAP county map]
Discussion

The characters used by J. A. Calder and D. B. O. Savile (1960) to separate var. porsildiana from var. pacifica overlap more significantly than do the characters that separate their subspecies, although inland populations of what has been called var. porsildiana gradually tend away from the morphology typical of coastal populations. Elven and Murray treated this taxon as a species distinct from Micranthes nelsoniana, because it apparently grows in stands mixed with other subspecies of M. nelsoniana without forming intermediates. The entire complex needs a thorough re-examination.

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

Varieties 6 (5 in the flora).

Although sometimes reported for North America, Saxifraga nelsoniana var. aestivalis (Fischer & C. A. Meyer) H. Ohba (S. aestivalis Fischer & C. A. Meyer) is found only in Eurasia.

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

Key
1. Inflorescences purple- or brown-tipped stipitate- glandular.
var. nelsoniana
1. Inflorescences tangled-hairy
→ 2
2. Leaf blade margins 9-12-toothed; capsules 6-12 mm; mostly Queen Charlotte Islands, adjacent coastal British Columbia.
var. carlottae
2. Leaf blade margins 12-18-toothed; capsules 3-8 mm; Oregon to Alaska and nw Canada
→ 3
3. Inflorescences somewhat lax, hairs appressed; Coast Ranges and Cascades, British Columbia, Oregon, Washington.
var. cascadensis
3. Inflorescences congested, hairs ascending; nw Canada, Alaska
→ 4
4. Leaf blades thick, fleshy; pistils connate most of their lengths; Aleutian Islands, Alaska.
var. insularis
4. Leaf blades thin, not fleshy; pistils connate to 3/4 their lengths; nw Canada, Alaska.
var. porsildiana
Source FNA vol. 8, p. 56. FNA vol. 8, p. 54.
Parent taxa Saxifragaceae > Micranthes > Micranthes nelsoniana Saxifragaceae > Micranthes
Sibling taxa
M. nelsoniana var. carlottae, M. nelsoniana var. cascadensis, M. nelsoniana var. insularis, M. nelsoniana var. nelsoniana
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. 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. tolmiei, M. unalaschcensis, M. virginiensis
Subordinate taxa
M. nelsoniana var. carlottae, M. nelsoniana var. cascadensis, M. nelsoniana var. insularis, M. nelsoniana var. nelsoniana, M. nelsoniana var. porsildiana
Synonyms Saxifraga punctata subsp. porsildiana, M. porsildiana, Saxifraga nelsoniana subsp. pacifica, Saxifraga nelsoniana var. pacifica, Saxifraga nelsoniana subsp. porsildiana, Saxifraga nelsoniana var. porsildiana, Saxifraga punctata subsp. pacifica, Saxifraga punctata var. pacifica, Saxifraga punctata var. porsildiana Saxifraga nelsoniana, Saxifraga punctata subsp. nelsoniana, Saxifraga punctata var. nelsoniana
Name authority (Calder & Savile) Gornall & H. Ohba: J. Bot. Res. Inst. Texas 2: 395. (2008) (D. Don) Small: in N. L. Britton et al., N. Amer. Fl. 22: 147. 1905 ,
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