Ivesia muirii |
Ivesia callida |
|
---|---|---|
granite mousetail, Muir's ivesia |
Tahquitz ivesia, Tahquitz mousetail |
|
Habit | Plants silvery, usually ± rosetted; taproot stout, sometimes fleshy. | Plants green, ± tufted to matted, often forming hanging clumps, sometimes rosetted. |
Stems | usually ± erect, sometimes nearly prostrate, 0.5–1.5(–2) dm. |
usually pendent or prostrate to ascending, sometimes nearly erect, 0.2–1.5 dm. |
Basal leaves | very tightly cylindric (mousetail-like, with individual leaflets scarcely distinguishable), 2–5(–10) cm; sheathing base densely strigose abaxially; petiole 0.2–0.8(–1) cm, hairs 0.5–1.5 mm; leaflets 25–40 per side, 0.4–1 mm, densely sericeous, glands obscured, lobes 2–5, obovate or oval to orbiculate, apex not setose. |
± loosely cylindric to weakly planar, 1–7 cm; sheathing base sparsely strigose abaxially; petiole 0.3–3 cm; lateral leaflets (1–)5–8 per side, slightly overlapping, elliptic to flabellate, 2–6(–7) mm, incised nearly to base into (0–)2–4 oblanceolate to elliptic lobes, apex sometimes ± setose, surfaces loosely long-strigose, sparsely glandular; terminal leaflets indistinct. |
Cauline leaves | (0–)1–2, paired if 2. |
(1–)2; blade reduced. |
Inflorescences | 10–30-flowered, 1–2(–3.5) cm diam.; glomerules usually 1. |
1–10(–15)-flowered, open, (0.5–)2–5 cm diam. |
Pedicels | 0.3–2(–3.5) mm. |
5–15 mm. |
Flowers | 5–6 mm diam.; epicalyx bractlets oblong to obovate, 0.5–1 mm; hypanthium shallowly cupulate, 0.5–1(–1.5) × 1.5–2.5 mm; sepals (1–)1.5–2.5 mm, acute; petals yellow, linear to oblanceolate or narrowly oblong, 1–2 mm; stamens 5, filaments 0.3–0.6 mm, anthers yellow, 0.4–0.6 mm; carpels 1–4, styles 0.7–1.2 mm. |
7–10 mm diam.; epicalyx bractlets 5, narrowly lanceolate, 1.5–3 mm; hypanthium patelliform, 0.5–1 × 2–3 mm; sepals 2–3.5 mm, acute; petals white, obovate, 2–3.5 mm; stamens 20, filaments 1.5–3 mm, anthers maroon, subrotund, 0.2–0.3 mm; carpels 4–8, styles 1.5–1.8 mm. |
Achenes | grayish brown, mottled with red, 1.6–2 mm. |
greenish white to light tan, 1.5 mm, smooth to lightly rugose, ± carunculate. |
Ivesia muirii |
Ivesia callida |
|
Phenology | Flowering summer. | Flowering summer. |
Habitat | Dry rocky slopes, fellfields, mostly in alpine conifer woodlands and tundra | Crevices of dry, rocky outcrops of granite, sometimes more or less vertical protected cliffs, in montane conifer woodlands |
Elevation | 2900–4000 m (9500–13100 ft) | 2400–2500 m (7900–8200 ft) |
Distribution |
CA
|
CA |
Discussion | Ivesia muirii is known from alpine areas in the Sierra Nevada. It is one of the more distinctive species of the genus, in its silvery mousetail-like leaves and usually tightly capitate inflorescences. Putative hybrids are known with I. lycopodioides (D. D. Keck 1938) and I. pygmaea (Center Basin area of Tulare County). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Ivesia callida occurs in the Tahquitz Peak area of the San Jacinto Wilderness Area, San Jacinto Mountains, Riverside County, where two populations are known (K. Berg 1983). Plants form tight mats in horizontal crevices and loose pendent clumps on vertical rock faces. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 236. | FNA vol. 9, p. 224. |
Parent taxa | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Ivesia > sect. Ivesia | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Ivesia > sect. Setosae |
Sibling taxa | ||
Synonyms | Potentilla muirii | Potentilla callida |
Name authority | A. Gray: Proc. Amer. Acad. Arts 8: 627. (1873) | (H. M. Hall) Rydberg: in N. L. Britton et al., N. Amer. Fl. 22: 286. (1908) |
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