Ivesia saxosa |
Ivesia santolinoides |
|
---|---|---|
rock ivesia, rock mousetail |
mouse tail ivesia, Sierra mousetail, silver mousetail, stellariopsis |
|
Habit | Plants green, ± tufted, often forming hanging clumps, sometimes rosetted. | Plants ± grayish to silvery. |
Stems | pendent or prostrate to ascending, 0.4–2.6(–3) dm. |
ascending to erect, (1–)1.5–4 dm. |
Basal leaves | planar, 2–15 cm; sheathing base not strigose abaxially; petiole 3–9 cm; lateral leaflets (1–)2–4(–7) per side, separate to slightly overlapping, obovate to orbiculate or flabellate, (3–)5–15(–22) mm, incised 1/4–3/4 to base into 5–15 broadly ovate teeth or oblanceolate lobes, sometimes also medially split to base (Kern Plateau), apex not setose, surfaces ± sparsely short-pilose, prominently glandular; terminal leaflets ± distinct. |
mousetail-like (individual leaflets scarcely distinguishable), 3–10 cm; sheathing base densely strigose abaxially; petiole 0.5–1.5 cm; leaflets 60–80 per side, 0.6–1.5 mm, lobes (0–)3–5, obovate to oval, densely villous. |
Cauline leaves | 1–2(–4); blade well developed. |
|
Inflorescences | (1–)3–30(–60)-flowered, open, (0.5–)2–8 cm diam. |
(10–)30–200-flowered, 3–8(–30) cm diam. |
Pedicels | (5–)10–30 mm. |
5–30 mm. |
Flowers | 6–12 mm diam.; epicalyx bractlets 5, broadly lanceolate to oblong, 1–2.5 mm; hypanthium patelliform, 0.5–1.5 × 2–4(–4.5) mm; sepals 2–4.5 mm, acute; petals yellow, oblanceolate to obovate, (1.5–)2–4 mm; stamens 15–35(–40), filaments 0.3–1 mm, anthers yellow, subrotund, 0.2–0.3(–0.5) mm; carpels (3–)10–20(–40), styles 1–2 mm. |
5–8 mm diam.; epicalyx bractlets oblong to broadly ovate or orbiculate, 0.2–0.5 mm; hypanthium 0.5–1.5 × 2–3 mm; sepals 1–2 mm, apex obtuse to acute; petals white, broadly obovate to orbiculate, 2–2.5 mm; stamens 15, filaments 1.2–1.8 mm, anthers purple, broadly obcordate to pouch-shaped, 0.3–0.4 mm; carpels 1, styles 2–3 mm. |
Achenes | greenish white to light tan, 1–1.8 mm, faintly rugose, ± carunculate. |
mottled grayish brown, 1.7–2 mm. |
2n | = 28. |
|
Ivesia saxosa |
Ivesia santolinoides |
|
Phenology | Flowering late spring–summer. | Flowering summer. |
Habitat | Dry, rocky outcrops of granitic or volcanic origin, usually crevices of more or less vertical protected cliffs or boulders, mainly in oak and conifer woodlands | Dry sandy granitic soil, decomposed granite accumulations, ledges and outcrops, in montane and subalpine conifer woodlands |
Elevation | 900–3300 m (3000–10800 ft) | 1500–3600 m (4900–11800 ft) |
Distribution |
CA; Mexico (Baja California)
|
CA
|
Discussion | Ivesia saxosa is encountered in the foothills and mountains of southeastern California from the White Mountains and adjacent eastern slopes of the Sierra Nevada of Mono County to the Transverse Ranges (including the Little San Bernardino Mountains) of Kern and San Bernardino counties. Populations on the Kern Plateau tend to have more dissected leaflets and may deserve recognition as a distinct variety. On the Peninsular Ranges, I. saxosa occurs in Riverside and San Diego counties and into northern Baja California, Mexico, as far south as the western slopes of the Sierra Juárez and Sierra San Pedro Mártir. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Ivesia santolinoides is found on loose granitic substrates in the Sierra Nevada, Transverse Ranges, and San Jacinto Mountains from El Dorado to Riverside counties. The species is easily recognized by its silvery mousetail-like leaves and erect, diffuse inflorescences with small, plumlike flowers. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 223. | FNA vol. 9, p. 246. |
Parent taxa | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Ivesia > sect. Setosae | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Ivesia > sect. Stellariopsis |
Sibling taxa | ||
Synonyms | Potentilla saxosa, P. acuminata, P. saxosa subsp. sierrae | Potentilla santolinoides, Stellariopsis santolinoides |
Name authority | (Lemmon ex Greene) Ertter: Syst. Bot. 14: 232. (1989) | A. Gray: Proc. Amer. Acad. Arts 6: 531. (1865) |
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