FNA: Ivesia argyrocoma vs. Ivesia argyrocoma var. argyrocoma

	Ivesia argyrocoma	Ivesia argyrocoma var. argyrocoma
	silver-hair ivesia, silverhair mousetail	silver-hair ivesia
Habit		Plants silvery; glands obscured.
Stems		prostrate to ascending, (0.3–)1–2.5(–3) dm.
Basal leaves		4–8(–10) cm; sheathing base sparsely to densely strigose abaxially; stipules lanceolate, 1–2 mm; petiole (0.5–)1–3 cm, hairs abundant, spreading, (1–)3–5 mm; leaflets 25–35 per side, tightly overlapping, (1–)2–3.5 mm, lobes 2–3, elliptic to obovate or oval, hairs dense, appressed to ascending, 0.5–1.5 mm.
Cauline leaves		(1–)2–3.
Inflorescences		(5–)10–30-flowered, (1–)1.5–4(–6) cm diam., flowers arranged in 1–several ± tight glomerules of 10–20(–30) flowers.
Pedicels		1–3 mm.
Flowers		7–9 mm diam.; epicalyx bractlets mostly linear to narrowly ovate, 0.8–2(–2.5) mm; hypanthium cupulate, (1–)1.5–2 × (2–)2.5–3(–3.5) mm, 1/2–2/3 as deep as wide; sepals sometimes purple-suffused, 2–3(–4) mm, acute; petals white, obovate, (2–)3–4(–4.5) mm; stamens 20, filaments flattened, 0.6–1.3 mm, anthers yellowish, 0.3–0.5 mm; carpels 4–8, styles 1.5–2.2 mm.
Achenes		brown, (1.5–)2–2.5 mm.

	Ivesia argyrocoma	Ivesia argyrocoma var. argyrocoma
Phenology		Flowering summer.
Habitat		Dry meadows, gravelly soil, in montane conifer woodlands
Elevation		1400–2300 m (4600–7500 ft)
Distribution	CA; nw Mexico [WildflowerSearch map] [BONAP county map]	CA
Discussion	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. Variety argyrocoma is found only on so-called pebble plains in the eastern San Bernardino Mountains, San Bernardino County. The filaments are significantly more flattened than those of other species of Ivesia and approach those that characterize Horkelia. (Discussion copyrighted by Flora of North America; reprinted with permission.)
Source	FNA vol. 9, p. 242.	FNA vol. 9, p. 242.
Parent taxa	Rosaceae > subfam. Rosoideae > tribe Potentilleae > Ivesia > sect. Unguiculatae	Rosaceae > subfam. Rosoideae > tribe Potentilleae > Ivesia > sect. Unguiculatae > Ivesia argyrocoma
Sibling taxa	I. aperta, I. arizonica, I. baileyi, I. callida, I. campestris, I. cryptocaulis, I. gordonii, I. jaegeri, I. kingii, I. longibracteata, I. lycopodioides, I. muirii, I. multifoliolata, I. paniculata, I. patellifera, I. pickeringii, I. pityocharis, I. pygmaea, I. rhypara, I. sabulosa, I. santolinoides, I. saxosa, I. sericoleuca, I. setosa, I. shockleyi, I. tweedyi, I. unguiculata, I. utahensis, I. webberi
Subordinate taxa	I. argyrocoma var. argyrocoma
Synonyms	Horkelia argyrocoma, Potentilla argyrocoma
Name authority	(Rydberg) Rydberg: in N. L. Britton et al., N. Amer. Fl. 22: 284. (1908)	unknown
Web links	Local Web sites: CalFlora, CalPhotos WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: CA Local Web sites: CalFlora, CalPhotos WildflowerSearch iNaturalist (observations) LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Ivesia argyrocoma var. argyrocoma

silver-hair ivesia, silverhair mousetail

silver-hair ivesia

Habit

Plants silvery; glands obscured.

Stems

prostrate to ascending, (0.3–)1–2.5(–3) dm.

Basal leaves

4–8(–10) cm; sheathing base sparsely to densely strigose abaxially;

stipules lanceolate, 1–2 mm;

petiole (0.5–)1–3 cm, hairs abundant, spreading, (1–)3–5 mm;

leaflets 25–35 per side, tightly overlapping, (1–)2–3.5 mm, lobes 2–3, elliptic to obovate or oval, hairs dense, appressed to ascending, 0.5–1.5 mm.

Cauline leaves

(1–)2–3.

Inflorescences

(5–)10–30-flowered, (1–)1.5–4(–6) cm diam., flowers arranged in 1–several ± tight glomerules of 10–20(–30) flowers.

Pedicels

1–3 mm.

Flowers

7–9 mm diam.;

epicalyx bractlets mostly linear to narrowly ovate, 0.8–2(–2.5) mm;

hypanthium cupulate, (1–)1.5–2 × (2–)2.5–3(–3.5) mm, 1/2–2/3 as deep as wide;

sepals sometimes purple-suffused, 2–3(–4) mm, acute;

petals white, obovate, (2–)3–4(–4.5) mm;

stamens 20, filaments flattened, 0.6–1.3 mm, anthers yellowish, 0.3–0.5 mm;

carpels 4–8, styles 1.5–2.2 mm.

Achenes

brown, (1.5–)2–2.5 mm.

Ivesia argyrocoma var. argyrocoma

Phenology

Flowering summer.

Habitat

Dry meadows, gravelly soil, in montane conifer woodlands

Elevation

1400–2300 m (4600–7500 ft)

Distribution

CA; nw Mexico

[WildflowerSearch map]

[BONAP county map]

Discussion

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.

Variety argyrocoma is found only on so-called pebble plains in the eastern San Bernardino Mountains, San Bernardino County. The filaments are significantly more flattened than those of other species of Ivesia and approach those that characterize Horkelia.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source

FNA vol. 9, p. 242.

Parent taxa

Rosaceae > subfam. Rosoideae > tribe Potentilleae > Ivesia > sect. Unguiculatae

Rosaceae > subfam. Rosoideae > tribe Potentilleae > Ivesia > sect. Unguiculatae > Ivesia argyrocoma

Sibling taxa

I. aperta, I. arizonica, I. baileyi, I. callida, I. campestris, I. cryptocaulis, I. gordonii, I. jaegeri, I. kingii, I. longibracteata, I. lycopodioides, I. muirii, I. multifoliolata, I. paniculata, I. patellifera, I. pickeringii, I. pityocharis, I. pygmaea, I. rhypara, I. sabulosa, I. santolinoides, I. saxosa, I. sericoleuca, I. setosa, I. shockleyi, I. tweedyi, I. unguiculata, I. utahensis, I. webberi

Subordinate taxa

I. argyrocoma var. argyrocoma

Synonyms

Horkelia argyrocoma, Potentilla argyrocoma

Name authority

(Rydberg) Rydberg: in N. L. Britton et al., N. Amer. Fl. 22: 284. (1908)

unknown

Web links

Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).

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Flora of North America species comparison

Ivesia argyrocoma

Ivesia argyrocoma var. argyrocoma

Ivesia argyrocoma

Ivesia argyrocoma var. argyrocoma