Ivesia argyrocoma
Ivesia utahensis
silver-hair ivesia, silverhair mousetail
Utah ivesia, Utah mousetail
prostrate to ascending, 0.5–1.5(–2) dm.
± tightly cylindric, 2–7(–9) cm; sheathing base glabrous abaxially;
petiole 0.5–2 cm, hairs 0.5–1 mm;
leaflets 15–20 per side, 2–4 mm, glabrate or sparsely short-hirsute, sparsely to densely glandular, lobes (2–)3–8, narrowly oblanceolate to obovate, apex not setose.
(0–)1, not paired.
(5–)10–30-flowered, 1–2.5(–5) cm diam.;
glomerules 1–few.
1–7 mm.
7–9 mm diam.;
epicalyx bractlets narrowly oblong to oval, 0.8–2 mm;
hypanthium shallowly cupulate, (1–)1.5–2 × 2.5–3.5 mm;
sepals (1.8–)2–3 mm, acute;
petals white, sometimes pink-tinged, oblanceolate to spatulate, 1.8–3 mm;
stamens 5, filaments 1.3–1.8 mm, anthers orangish to reddish brown, 0.4–0.6 mm;
carpels (1–)2–4, styles 1.5–2 mm.
yellowish green to light tan or gray-brown, 1.7–1.9 mm.
Ivesia argyrocoma
Ivesia utahensis
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 utahensis is known from the Wasatch and adjacent Uinta Mountains in northern Utah. The species stands as the white-petaled counterpart to the yellow-petaled Sierran I. lycopodioides, possibly indicating a common ancestral stock that was once more continuous across the Great Basin.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CalFlora
WildflowerSearch
iNaturalist
USDA Plants Database
