3. Micranthes odontoloma (Piper) A. Heller, Muhlenbergia. 8: 60. 1912.
Saxifraga odontoloma Piper, Smithsonian Misc. Collect. 50: 200. 1907, based on S. odontophylla Piper, Contr. U.S. Natl. Herb. 11: 314. 1906, not Wallich ex Sternberg 1831
Plants solitary or sometimes grouped, rhizomatous. Leaves basal; petiole rounded, 2-30 cm; blade round, 7-40 cm, thin to slightly fleshy, base cordate to truncate, margins regularly dentate, eciliate, surfaces sparsely brownish hairy abaxially, glabrous adaxially. Inflorescences 10-30+-flowered, open, lax, flat-topped thyrses, 20-65(-85) cm, glabrous proximally, purple-tipped subsessile-glandular distally. Flowers: sepals reflexed, ovate to elliptic; petals white, each with 2 basal yellow spots, round to broadly elliptic, clawed, 3-4.5 mm, longer than sepals; filaments strongly club-shaped, (to 6 mm); pistils connate ca. 1/2 their lengths; ovary superior. Capsules green to purple, ± folliclelike. 2n = 24, 48.
Flowering summer-early autumn. Wet meadows and stream banks; 1500-4000 m; Alta., B.C.; Ariz., Calif., Colo., Idaho, Mont., Nev., N.Mex., Oreg., Utah, Wash., Wyo.