[Saxifraga debilis Engelm. ex A. Gray, moreSaxifraga hyperborea subsp. debilis (Engelm. ex A. Gray) A.& D. Löve & Kapoor, Saxifraga rivularis subsp. flexuosa (Sternb.) Gjaerev., Saxifraga rivularis var. debilis (Engelm. ex A. Gray) Dorn, Saxifraga rivularis var. flexuosa (Sternb.) Engl. & Irmsch.]
Plants usually densely tufted, sometimes loosely so, not stoloniferous, not rhizomatous. Leaves basal and cauline, (3-5, proximal similar to basal); petiole ± flattened, 5-70 mm; blade round or reniform, (3-)5-7-lobed (lobes obtuse), (3-)4.5-6.7(-10.3) mm, slightly fleshy, margins entire, eciliate, surfaces glabrous. Inflorescences 2-3(-5)-flowered, capitate cymes, sometimes solitary flowers, (flowers subsessile), (3-)6.7-9(-19.4) cm, tangled, nonglandular-hairy; bracts petiolate. Flowers (hypanthium V-shaped in longisection, glabrous or sparsely short stipitate-glandular); sepals erect, oblong to ovate, (0.7-1 mm wide), margins eciliate, surfaces abaxially glabrous; petals white to pale purple, not spotted, oblong, (1.7-)3-4.4(-6.2) mm, ± equaling sepals; ovary 1/2 inferior. 2n = 26. Flowering summer. Alpine meadows, snow beds, open gravel and silt, seepage areas, stream and lake margins, shady taluses, ravines or cliffs; 2500-4000 m; Colo., Mont., N.Mex., Utah, Wyo. Saxifraga debilis is known only from the central and southern Rocky Mountains, where it is often called S. rivularis (a species not present in the area). Its V-shaped (in longisection), glabrous or sparsely short stipitate-glandular hypanthia, and larger, more-lobed leaves (similar to S. bracteata in this) distinguish it from S. hyperborea, which is sometimes sympatric (M. H. Jørgensen et al. 2006).
Plant: perennial herb Leaves: basal and cauline, reduced upwards; blades circular to broader than long, 0.4-1.5 cm long, the base usually cordate, the margin usually 3-5 lobed; petioles 0.5-3.5 cm long, flattened INFLORESCENCE: 3-10 cm tall, very sparsely covered with pink to purple-tipped glandular hairs Flowers: usually 1-3; sepals erect, elliptic-ovate; petals 2-6 mm long, longer than sepals, elliptic-obovate; filaments lanceolate; ovary more than half inferior in flower, appearing more superior in fruit; nectaries inconspicuous or 0 Fruit: FRUITS 2(-3) valved; SEEDS smooth to ridged Misc: Moist crevices, shaded, rocky areas; above 3050 m (10000 ft); Jul-Aug Notes: CAUDEX fragile; bulblets few REFERENCES: Elvander, Patrick. 1992. Saxifragaceae. Ariz.-Nev. Acad. Sci. 26(1)2.
Rhizomatous; stems tufted, 2-10 cm; lower lvs long- petioled, the blade reniform in outline, 4-13 mm wide, 3-5(-7)-lobed; upper lvs on shorter petioles, smaller, less cleft or entire, without bulblets; fls 1-4, long-pediceled, white; pet 3-5 mm; 2n=26, 52, 56. Circumboreal, s. to e. Que., the White Mts., of N.H., and Mont. July.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.