Micranthes rhomboidea

(Greene) Small

in N. L. Britton et al., N. Amer. Fl. 22: 136. 1905 ,.

Common names: Diamond-leaf saxifrage
Basionym: Saxifraga rhomboidea Greene Pittonia 3: 343. 1898
Synonyms: Saxifraga austrina (A. Nelson) A. Nelson Saxifraga rhomboidea var. austrina A. Nelson Saxifraga rhomboidea var. franciscana (Small) Kearney & Peebles
Treatment appears in FNA Volume 8. Treatment on page 69. Mentioned on page 51, 65.

Plants solitary or tufted, with bulbils on caudices. Leaves basal; petiole flattened, 1–3 cm; blade broadly ovate to triangular, 1–3 cm, fleshy, base attenuate, margins coarsely serrate, ciliate, surfaces sparsely to moderately tangled, reddish brown-hairy abaxially, glabrous adaxially. Inflorescences (5–)10–40-flowered, congested, ± glomerate or capitate thyrses, 4–20 cm, usually densely yellow- to cream-tipped stipitate-glandular. Flowers: sepals ascending, ovate; petals white, not spotted, oblong to elliptic, clawed, 2–4 mm, 1.5+ times as long as sepals; filaments linear, flattened; pistils connate to 1/2 their lengths; ovary inferior, appearing more superior in fruit. Capsules purple, folliclelike. 2n = 20, 38, 40, 56.

Phenology: Flowering late spring–summer.
Habitat: Subalpine and alpine meadows
Elevation: 1500-4600 m


V8 135-distribution-map.gif

Ariz., Colo., Idaho, Mont., N.Mex., Utah, Wyo.


Micranthes rhomboidea is somewhat polymorphic; variants have been given taxonomic designations with little consistency. The chromosome number variation needs thorough study, as in other species of Micranthes, because no obvious correlations with morphology or geographic distribution are known (B. L. Bethers 1973). Reports from Canada (Alberta, Saskatchewan) were rejected as misidentifications of M. occidentalis.

Selected References


Lower Taxa

... more about "Micranthes rhomboidea"
Luc Brouillet +  and Patrick E. Elvander† +
(Greene) Small +
Saxifraga rhomboidea +
Diamond-leaf saxifrage +
Ariz. +, Colo. +, Idaho +, Mont. +, N.Mex. +, Utah +  and Wyo. +
1500-4600 m +
Subalpine and alpine meadows +
Flowering late spring–summer. +
in N. L. Britton et al., N. Amer. Fl. +
Saxifraga austrina +, Saxifraga rhomboidea var. austrina +  and Saxifraga rhomboidea var. franciscana +
Micranthes rhomboidea +
Micranthes +
species +