Ivesia utahensis |
Ivesia jaegeri |
|
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Utah ivesia, Utah mousetail |
Jaeger's ivesia, Jaeger's mousetail |
|
Habit | Plants green, rosetted to tufted; taproot proximally enlarged, not fleshy. | Plants green, ± tufted to ± matted, often forming hanging clumps, sometimes rosetted. |
Stems | prostrate to ascending, 0.5–1.5(–2) dm. |
pendent or prostrate to ascending, 0.3–1.5 dm. |
Basal leaves | ± tightly cylindric, 2–7(–9) cm; sheathing base glabrous abaxially; petiole 0.5–2 cm, hairs 0.5–1 mm; leaflets 15–20 per side, 2–4 mm, glabrate or sparsely short-hirsute, sparsely to densely glandular, lobes (2–)3–8, narrowly oblanceolate to obovate, apex not setose. |
± loosely cylindric to weakly planar, 2–8(–10) cm; sheathing base not or sparsely strigose abaxially; petiole 0.5–4 cm; lateral leaflets (1–)4–6(–8) per side, ± overlapping at least distally, ± flabellate, 2–6(–7) mm, incised nearly to base into 3–6 oblanceolate to narrowly obovate lobes, apex not or scarcely setose, surfaces ± sparsely short-pilose, ± glandular; terminal leaflets indistinct. |
Cauline leaves | (0–)1, not paired. |
(1–)2; blade well developed. |
Inflorescences | (5–)10–30-flowered, 1–2.5(–5) cm diam.; glomerules 1–few. |
(1–)3–15-flowered, open, (0.5–)1.5–4(–7) cm diam. |
Pedicels | 1–7 mm. |
5–30 mm. |
Flowers | 7–9 mm diam.; epicalyx bractlets narrowly oblong to oval, 0.8–2 mm; hypanthium shallowly cupulate, (1–)1.5–2 × 2.5–3.5 mm; sepals (1.8–)2–3 mm, acute; petals white, sometimes pink-tinged, oblanceolate to spatulate, 1.8–3 mm; stamens 5, filaments 1.3–1.8 mm, anthers orangish to reddish brown, 0.4–0.6 mm; carpels (1–)2–4, styles 1.5–2 mm. |
5–11 mm diam.; epicalyx bractlets 5, lanceolate, 1–2 mm; hypanthium patelliform, 1 × 2–4 mm; sepals 2–3 mm, ± acute; petals yellow, narrowly oblanceolate, 1.5–2 mm; stamens 20, filaments 1–1.5(–1.8) mm, anthers yellow, subrotund, 0.2–0.3 mm; carpels 3–8, styles 1.5–2 mm. |
Achenes | yellowish green to light tan or gray-brown, 1.7–1.9 mm. |
tan to light brown, 1–2 mm, ± rugose, ± carunculate. |
Ivesia utahensis |
Ivesia jaegeri |
|
Phenology | Flowering summer. | Flowering summer. |
Habitat | Talus slopes, bare ridges, in high-elevation sagebrush communities, subalpine to alpine conifer woodlands | Dry, rocky outcrops of limestone origin, usually crevices of more or less vertical protected cliffs or boulders, mainly in conifer woodlands |
Elevation | 3200–3700 m (10500–12100 ft) | 1600–3600 m (5200–11800 ft) |
Distribution |
UT |
CA; NV |
Discussion | Of conservation concern. Ivesia utahensis is known from the Wasatch and adjacent Uinta Mountains in northern Utah. The species stands as the white-petaled counterpart to the yellow-petaled Sierran I. lycopodioides, possibly indicating a common ancestral stock that was once more continuous across the Great Basin. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Ivesia jaegeri is known only from the Spring Mountains, Clark County, Nevada, and the Clark Mountains, San Bernardino County, California. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 233. | FNA vol. 9, p. 223. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Potentilla utahensis | Potentilla jaegeri |
Name authority | S. Watson: Proc. Amer. Acad. Arts 17: 371. (1882) | Munz & I. M. Johnston: Bull. Torrey Bot. Club 56: 165. (1929) |
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