Ivesia paniculata |
Ivesia shockleyi |
|||||
---|---|---|---|---|---|---|
Ash Creek ivesia, Ash Creek mousetail |
Shockley's ivesia, sky mousetail |
|||||
Habit | Plants grayish, ± matted. | Plants green to grayish green, ± densely matted. | ||||
Stems | ± prostrate, 0.4–1.5(–2) dm. |
prostrate to ascending, 0.2–1.5 dm. |
||||
Basal leaves | tightly cylindric, (1.5–)2–5(–7) cm; sheathing base densely hairy abaxially; petiole 0.5–4 cm; lateral leaflets (5–)8–15 per side, overlapping at least distally, ± flabellate, 0.5–2 mm, incised to base or nearly so into (0–)3–8(–15) elliptic to narrowly obovate lobes, apex not or obscurely setose, surfaces densely hirsute, cryptically glandular; terminal leaflets indistinct. |
tightly to loosely cylindric, (1–)2–12(–14) cm; sheathing base strigose to hirsute abaxially; petiole 0.5–4 cm; lateral leaflets (3–)5–15(–18) per side, separate to overlapping at least distally, ± flabellate, 1–4(–6) mm, incised to base or nearly so into 2–10(–12) oblanceolate to obovate or elliptic lobes, apex sometimes setose, surfaces ± sparsely hirsute, ± glandular; terminal leaflets indistinct. |
||||
Cauline leaves | (0–)1; blade reduced. |
(0–)1; blade vestigial or reduced. |
||||
Inflorescences | 20–200-flowered, congested, (1–)1.5–6(–10) cm diam. |
2–20-flowered, ± open, 0.5–4(–6) cm diam. |
||||
Pedicels | 1.5–6 mm. |
3–10(–12) mm. |
||||
Flowers | 4–6 mm diam.; epicalyx bractlets 5, lanceolate to elliptic, 0.6–1.5(–2) mm; hypanthium shallowly cupulate, 1 × 2–3 mm; sepals (1–)1.5–2.5(–3) mm, acute; petals white to pale yellowish, linear, 1 mm; stamens 5, filaments 0.3–1 mm, anthers yellow with maroon margins, ovate, 0.3–0.5 mm; carpels 1–2(–3), styles 0.7–1.8 mm. |
5–10 mm diam.; epicalyx bractlets 5, elliptic or narrowly oblong to ovate, 0.7–2(–3) mm; hypanthium patelliform, 1–2 × 2.5–4.5(–5) mm; sepals 1.5–3.5(–4) mm, acute to obtuse; petals ± yellow, oblanceolate to spatulate or narrowly obovate, 1–3 mm; stamens 5, filaments 0.8–1.8 mm, anthers yellow, oblong, 0.4–0.9 mm; carpels 2–5(–6), styles 1.8–2.5 mm. |
||||
Achenes | brown, 0.8–1.5 mm, smooth, prominently carunculate. |
greenish cream to light brown, 1.5–2.2(–2.5) mm, smooth, prominently carunculate. |
||||
Ivesia paniculata |
Ivesia shockleyi |
|||||
Phenology | Flowering summer. | |||||
Habitat | Dry shallow volcanic ash and cinders atop volcanic bedrock, open sagebrush communities, adjacent conifer woodlands | |||||
Elevation | 1500–1800 m (4900–5900 ft) | |||||
Distribution |
CA |
CA; NV; OR; UT
|
||||
Discussion | Of conservation concern. Ivesia paniculata is known only from the Ash Valley area of Lassen County. The distinctions between I. paniculata and I. rhypara are perhaps on the same scale as variation among disjunct population clusters of I. rhypara, but no taxonomic adjustments are proposed at this time. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Varieties 2 (2 in the flora). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
||||
Key |
|
|||||
Source | FNA vol. 9, p. 229. | FNA vol. 9, p. 227. | ||||
Parent taxa | ||||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Potentilla shockleyi | |||||
Name authority | T. W. Nelson & J. P. Nelson: Brittonia 33: 165, fig. 1. (1981) | S. Watson: Proc. Amer. Acad. Arts 23: 263. (1888) | ||||
Web links |