Ivesia setosa
Ivesia utahensis
bristly ivesia
Utah ivesia, Utah mousetail
± ascending to nearly erect, 0.7–2.5(–2.8) dm.
prostrate to ascending, 0.5–1.5(–2) dm.
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, 2–7(–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;
blade vestigial.
(0–)1, not paired.
(1–)5–15(–30)-flowered, ± open, 1–6(–12) cm diam.
(5–)10–30-flowered, 1–2.5(–5) cm diam.;
glomerules 1–few.
5–15(–20) mm.
1–7 mm.
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.
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.
greenish white to light tan, 1.7–2 mm, smooth, ± carunculate.
yellowish green to light tan or gray-brown, 1.7–1.9 mm.
Ivesia setosa
Ivesia utahensis
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.)
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
