Home/Species/ Swamp Saxifrage

Micranthes apetala

(Piper) Small

Swamp Saxifrage

G3Vulnerable (G3Q) Found in 3 roadless areas NatureServe Explorer →

G3VulnerableGlobal Rank

Identity

Unique IDELEMENT_GLOBAL.2.144383

Element CodePDSAX0U220

Record TypeSPECIES

ClassificationSpecies

Classification StatusStandard

Name CategoryVascular Plant

Endemicendemic to a single nation

KingdomPlantae

PhylumAnthophyta

ClassDicotyledoneae

OrderRosales

FamilySaxifragaceae

GenusMicranthes

Synonyms

Saxifraga apetalaPiperSaxifraga integrifolia var. apetala(Piper) M.E. Jones

Concept Reference

Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.

Taxonomic Comments

Saxifraga apetala has been interpreted as a variety of S. integrifolia and of S. columbiana (Elvander, 1984). Kartesz (5/98 draft) recognizes S. apetala as distinct. FNA (vol. 8, 2009) transfers S. apetala to Micranthes apetala.

Conservation Status

Review Date1991-08-05

Change Date1991-08-05

Edition Date1991-05-29

Edition AuthorsBuckley, A.

Number of Occurrences6 - 20

Rank Reasons

Range restricted and distjunct. Few identified populations. No high threats.

Range Extent Comments

Range about 10,000+ sq. mi. Occurs along the eastern slope of Washington Cascades (Okanogan to Yakima Counties) and disjunct in Montana.

Occurrences Comments

But could be C. About 10 populations identified in Washington, disjunct also in Montana.

Ecology & Habitat

Description

Tiny Swamp Saxifrage is a short-lived perennial herb with erect, leafless stems that are 5-10 cm high and arising from a short, often bulblet-bearing rhizome. Rosette leaves are 13-35 mm long and are egg-shaped with a short, broad petiole. The leaves have scattered, long, white or brown hairs, while the stem is densely covered with white, gland-tipped hairs. 5-15 short-stalked flowers are borne in a congested, terminal, egg-shaped cluster. Each saucer-shaped flower has 5 separate, ascending, green sepals that are 1-3 mm long and 10 white stamens attached to the middle of the ovary. The top half of the ovary forms a lobed disk with usually 2 short styles.

Diagnostic Characteristics

SAXIFRAGA has many similar-appearing species; a technical key and hand lens are necessary for identification. S. OREGANA VAR SUBAPETALA also lacks petals, but the stamens are purple. S. INTEGRIFOLIA is also very similar, but it has petals and the inflorescence is less congested. S. RHOMBOIDEA is the most common high-elevation species, but it also has petals.

Habitat

Vernally wet meadows, on banks of emphemeral streams, in wet depressions on mountain slopes; 600 - 2800 m.

Other Nations (1)

United StatesN3

Province	Rank	Native
Oregon	SNR	Yes
Washington	S3	Yes
Montana	S2	Yes

Plant Characteristics

Economic Value (Genus)No

Roadless Areas (3)

Washington (3)

Area	Forest	Acres
Blue Slide	Wenatchee National Forest	17,505
Chelan	Wenatchee National Forest	74,650
Lion Rock	Wenatchee National Forest	4,692

References (5)

Elvander, P.E. 1984. The taxonomy of Saxifraga (Saxifragaceae) section Boraphila subsection Integrifoliae in western North America. Systematic Botany Monographs 3: 1-44.
Flora of North America Editorial Committee (FNA). 2009. Flora of North America north of Mexico. Vol. 8. Magnoliophyta: Paeoniaceae to Ericaceae. Oxford University Press, New York. xxiv + 585 pp.
Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Stubbs, R.L., D.E. Soltis, and N. Cellinese. 2018. The future of cold- adapted plants in changing climates: Micranthes (Saxifragaceae) as a case study. Ecology and Evolution 8:7164-7177.
Stubbs, R.L., R.A. Folk, D.E. Soltis, and N. Cellinese. 2020. Diversification in the Arctic: Biogeography and Systematics of the North American Micranthes (Saxifragaceae). Systematic Botany 45(4): 802-811.