Ivesia santolinoides |
Ivesia baileyi |
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mouse tail ivesia, Sierra mousetail, silver mousetail, stellariopsis |
Bailey's ivesia, Owyhee ivesia |
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Habit | Plants ± grayish to silvery. | Plants green, ± tufted, often forming hanging clumps, sometimes rosetted. | ||||
Stems | ascending to erect, (1–)1.5–4 dm. |
pendent or prostrate to ascending, 0.5–2(–2.5) dm. |
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Basal leaves | 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. |
planar, 3–12(–18) cm; sheathing base not or sparsely strigose abaxially; petiole 1–8 cm; lateral leaflets 2–6(–10) per side, separate to slightly overlapping distally, ovate or obovate to flabellate, 4–15(–25) mm, incised 1/4–3/4 to base into 3–11(–15) ovate to oblanceolate teeth or lobes, apex not setose, surfaces ± sparsely short-pilose or hirsute, ± glandular; terminal leaflets ± distinct. |
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Cauline leaves | 1–2; blade reduced. |
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Inflorescences | (10–)30–200-flowered, 3–8(–30) cm diam. |
(1–)5–40-flowered, open, (1–)1.5–8(–10) cm diam. |
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Pedicels | 5–30 mm. |
2–15(–30) mm. |
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Flowers | 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. |
4–10 mm diam.; epicalyx bractlets 5, narrowly lanceolate to ovate, 0.8–2.5 mm; hypanthium patelliform, 0.5–2 × 2–4 mm; sepals (1.2–)1.5–4 mm, acute; petals white or pale yellow, oblanceolate to narrowly spatulate, 1.5–2.5 mm; stamens 5, filaments 0.5–1.1 mm, anthers yellow, sometimes with reddish margins, oblong, 0.4–0.7 mm; carpels (1–)3–8, styles 0.9–1.8 mm. |
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Achenes | mottled grayish brown, 1.7–2 mm. |
greenish white to light tan, 1.5–2 mm, smooth or rugose, ± carunculate. |
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2n | = 28. |
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Ivesia santolinoides |
Ivesia baileyi |
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Phenology | Flowering summer. | |||||
Habitat | Dry sandy granitic soil, decomposed granite accumulations, ledges and outcrops, in montane and subalpine conifer woodlands | |||||
Elevation | 1500–3600 m (4900–11800 ft) | |||||
Distribution |
CA
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CA; ID; NV; OR
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Discussion | 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.) |
Varieties 2 (2 in the flora). The two varieties accepted here were not recognized by D. D. Keck (1938), who instead treated Ivesia setosa as a variety of I. baileyi. Field investigations confirm that the three entities are reasonably distinct morphologically, with intergradation where their otherwise distinct ranges overlap in central Nevada. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 9, p. 246. | FNA vol. 9, p. 226. | ||||
Parent taxa | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Ivesia > sect. Stellariopsis | Rosaceae > subfam. Rosoideae > tribe Potentilleae > Ivesia > sect. Setosae | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Potentilla santolinoides, Stellariopsis santolinoides | Potentilla baileyi | ||||
Name authority | A. Gray: Proc. Amer. Acad. Arts 6: 531. (1865) | S. Watson: Botany (Fortieth Parallel), 90. (1871) | ||||
Web links |