Ivesia argyrocoma
Ivesia unguiculata
silver-hair ivesia, silverhair mousetail
Yosemite ivesia, Yosemite mousetail
decumbent to ascending, 1–3.5 dm.
(4–)7–15 cm; sheathing base ± glabrous abaxially;
stipules linear, 3–6 mm;
petiole (0.3–)0.5–4(–5) cm, hairs sparse to abundant, ascending to spreading, 1–2 mm;
leaflets 15–20(–25) per side, loosely overlapping, 3–6 mm, lobes 3–8, linear to oblanceolate, hairs sparse to abundant, spreading, 1–2 mm.
3–6.
(15–)30–100(–200)-flowered, (1–)1.5–4(–8) cm diam., flowers mostly arranged in 1–several loose to tight glomerules of 5–10 flowers.
1–3 mm.
6–9 mm diam.;
epicalyx bractlets linear or narrowly lanceolate to elliptic or narrowly oblong, 1.2–2(–3) mm;
hypanthium shallowly turbinate, 1.5–2.5 × 2–3(–3.5) mm, often nearly as deep as wide;
sepals heavily purple-mottled, (1.5–)2–3(–3.5) mm, acute;
petals white, often tinged with pink, oblanceolate to spatulate or obovate, 3–4 mm;
stamens 10–15, filaments filiform, 0.6–1.1 mm, anthers maroon, 0.3–0.5 mm;
carpels (1–)3–9, styles 1.4–2 mm.
light brown, 1.2–1.5 mm.
Ivesia argyrocoma
Ivesia unguiculata
Varieties 2 (1 in the flora).
Plants from the central Sierra San Pedro Mártir in northern Baja California belong to var. moranii Ertter & Reveal, which may be distinguished by its compact stature (to 0.5 dm), densely villous basal stipules 2–4 mm, decumbent stems 2–7 cm that are stipitate-glandular under the villous indumentum, and solitary, loosely congested cyme. The petals are oblanceolate to narrowly obovate and 2.5–3.5 mm. The grayish, faintly mottled achenes are 1.3–2 mm.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Of conservation concern.
Ivesia unguiculata is found in mid-elevation meadows of the central Sierra Nevada, mostly north of the Kings River. The distinctive deep red to purplish coloration of the inflorescence, and the plant in general, can make patches of this species conspicuous as a smoky purplish haze in meadows. The shape and color of the inflorescences are similar to those of the sympatric Horkelia fusca var. parviflora, suggesting shared pollinators.
The description and illustration by J. D. Hooker (1881), supposedly of Potentilla (Ivesia) unguiculata, were based actually on material grown from seed of I. sericoleuca due to initial confusion of the two species (W. H. Brewer et al. 1876–1880, vol. 1).
The type (Kellogg s.n., CAS) of Potentilla ciliata Greene (not Rafinesque) is unquestionably this species; however, the purported locality (Owens Valley, Inyo County) is dubious and most likely an error in the labeling of the specimen by the collector.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CalFlora
WildflowerSearch
iNaturalist
USDA Plants Database
