Ivesia setosa |
Ivesia rhypara |
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bristly ivesia |
grimy ivesia, grimy mousetail |
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Habit | Plants green, tufted to ± densely matted. | Plants grayish, ± matted. | ||||
Stems | ± ascending to nearly erect, 0.7–2.5(–2.8) dm. |
± prostrate, (0.1–)0.2–1.5(–2) dm. |
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Basal leaves | weakly planar to loosely cylindric, 5–9(–12) cm; sheathing base ± strigose abaxially; petiole 1–8 cm; lateral leaflets 5–10 per side, separate to overlapping distally, ± flabellate, 2–8 mm, incised ± 3/4 to base, sometimes nearly to base, into (3–)7–11 ovate teeth to narrowly obovate lobes, apex usually ± setose, surfaces ± sparsely hirsute, conspicuously glandular; terminal leaflets ± indistinct. |
tightly cylindric, 2–10 cm; sheathing base densely hairy abaxially; petiole 0.5–4(–10) cm; lateral leaflets 4–10(–15) per side, overlapping at least distally, ± flabellate, 0.5–3(–4) mm, incised to base or nearly so into (0–)2–4(–9) elliptic to obovate or orbiculate lobes, apex usually not setose, surfaces densely hirsute, cryptically glandular; terminal leaflets indistinct. |
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Cauline leaves | (0–)1; blade vestigial. |
(0–)1; blade vestigial. |
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Inflorescences | (1–)5–15(–30)-flowered, ± open, 1–6(–12) cm diam. |
5–60(–100)-flowered, congested, 0.5–5(–7) cm diam. |
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Pedicels | 5–15(–20) mm. |
1.5–4(–8) mm. |
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Flowers | 7–10 mm diam.; epicalyx bractlets 5, lanceolate, 1.3–2.5(–3) mm; hypanthium patelliform, (1–)1.5–2 × 2–3.5(–4) mm; sepals (1.5–)2–3.5 mm, ± acute; petals yellow, oblanceolate to narrowly spatulate, 1.5–2.5 mm; stamens 5, filaments 0.8–1.5 mm, anthers yellow, oblong, 0.4–0.7 mm; carpels 2–8, styles 1.2–2 mm. |
4–8 mm diam.; epicalyx bractlets 5, linear to elliptic or narrowly ovate, 0.8–1.6(–2.1) mm; hypanthium patelliform to shallowly cupulate, 1–1.5 × (1.5–)2–3(–3.5) mm; sepals 1.4–2.5(–2.8) mm, acute; petals white to pale yellowish, linear to narrowly oblanceolate, 1–1.5 mm; stamens 5, filaments 0.6–1.8 mm, anthers maroon or yellow with maroon margins, oblong, 0.3–0.6 mm; carpels 1–2(–4), styles 1–1.5 mm. |
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Achenes | greenish white to light tan, 1.7–2 mm, smooth, ± carunculate. |
brown, 1.2–1.6(–2) mm, smooth, prominently carunculate. |
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Ivesia setosa |
Ivesia rhypara |
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Phenology | Flowering summer. | |||||
Habitat | Dry, rocky talus slopes, boulders and outcrops, most often but not always of calcareous origin, occasionally away from immediate outcrops, sagebrush communities, conifer woodlands | |||||
Elevation | 1800–2600(–3100) m (5900–8500(–10200) ft) | |||||
Distribution |
NV; UT |
NV; OR
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Discussion | Ivesia setosa occurs mostly to the east and south of I. baileyi, from southeastern Humboldt and Churchill counties to Elko, White Pine, and northern Nye counties, Nevada, and in the Deep Creek Range of western Utah. It represents a transition between the planar-leaved, chasmophytic members of sect. Setosae and the cylindric-leaved, matted species of flatter sites. Stems of I. setosa are more generally erect than in other species in the section, and the usually calcareous substrate is noteworthy. The deeply incised (usually not quite to base) leaflets are somewhat intermediate between the toothed leaflets of I. baileyi and the leaflets of I. shockleyi that are incised to the base into separate lobes. The individual leaflets of both I. baileyi and I. setosa are more or less flat and distichously paired; in I. shockleyi, groups of leaflet lobes are folded over onto each other, giving a verticillate appearance to the leaflet arrangement. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Varieties 2 (2 in the flora). Ivesia rhypara forms densely hairy mats or mounds on isolated edaphic sites in the northern Great Basin. Only one of the widely disjunct population clusters is recognized as a distinct variety; the others have general differences in gestalt, but no significant distinctions have been determined (B. Ertter 1989). Isozyme analysis likewise does not show significant differences (T. Kaye et al., unpubl., BLM and Oregon Dept. of Agriculture, 1991). Reproductive studies by D. Wiens (pers. comm.) show low seed set (ca. 5% in var. rhypara, somewhat higher in var. shellyi), possibly indicating a deleterious genetic load. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 9, p. 227. | FNA vol. 9, p. 228. | ||||
Parent taxa | ||||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | I. baileyi var. setosa, Potentilla baileyi var. setosa | |||||
Name authority | (S. Watson) Rydberg: in N. L. Britton et al., N. Amer. Fl. 22: 290. (1908) | Ertter & Reveal: Madroño 24: 224, fig. 1. (1977) | ||||
Web links |