FNA: Ivesia argyrocoma vs. Ivesia pityocharis

	Ivesia argyrocoma	Ivesia pityocharis
	silver-hair ivesia, silverhair mousetail	pine nut mountain mousetail, pine nut mountains ivesia
Habit		Plants grayish green to silvery, sometimes reddish tinged; glands sparse.
Stems		prostrate-decumbent to ascending, 0.5–2(–3) dm.
Basal leaves		6–12(–15) cm; sheathing base weakly strigose abaxially; stipules absent; petiole (1–)1.5–2.5(–3) cm, hairs abundant, ascending to spreading, 1–4 mm; leaflets 15–25 per side, loosely overlapping, (1.5–)2–7 mm, lobes 0–4(–6), lanceolate or oblanceolate to elliptic, hairs abundant, spreading to ascending, 1–3 mm.
Cauline leaves		2–5.
Inflorescences		(7–)15–50-flowered, 2–8 cm diam., flowers arranged individually and/or in several to many loose few-flowered glomerules.
Pedicels		(3–)6–15(–22) mm.
Flowers		8–13 mm diam.; epicalyx bractlets lanceolate to elliptic, 2–3 mm; hypanthium patelliform to shallowly cupulate, 1.5–2.5 × 3–4.5 mm, ± 1/2 as deep as wide; sepals often purple-suffused, 2.3–4(–5) mm, acute; petals white, broadly spatulate or obovate to orbiculate, (2.8–)3–5(–6) mm; stamens 20, filaments filiform, (1–)1.5–3 mm, anthers light pink, 0.3–0.5 mm; carpels 8–20, styles 2.2–3 mm.
Achenes		light brown, 1.2–1.3 mm.

	Ivesia argyrocoma	Ivesia pityocharis
Phenology		Flowering summer.
Habitat		Vernally saturated meadows, in sagebrush communities
Elevation		2100–2700 m (6900–8900 ft)
Distribution	CA; nw Mexico [WildflowerSearch map] [BONAP county map]	NV [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. Ivesia pityocharis is known only from the Pine Nut Mountains, Douglas County. Plants are somewhat intermediate between those of I. kingii and I. sericoleuca in having relatively shallow hypanthia and loosely sericeous vestiture. Hairs on petioles and stem bases of I. pityocharis are to 4 mm; those of I. kingii are 1 mm and generally appressed-ascending. (Discussion copyrighted by Flora of North America; reprinted with permission.)
Source	FNA vol. 9, p. 242.	FNA vol. 9, p. 241.
Parent taxa	Rosaceae > subfam. Rosoideae > tribe Potentilleae > Ivesia > sect. Unguiculatae	Rosaceae > subfam. Rosoideae > tribe Potentilleae > Ivesia > sect. Unguiculatae
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	I. aperta, I. argyrocoma, 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. 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)	Ertter: Syst. Bot. 14: 241, fig. 6. (1989)
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 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

Ivesia pityocharis

silver-hair ivesia, silverhair mousetail

pine nut mountain mousetail, pine nut mountains ivesia

Habit

Plants grayish green to silvery, sometimes reddish tinged; glands sparse.

Stems

prostrate-decumbent to ascending, 0.5–2(–3) dm.

Basal leaves

6–12(–15) cm; sheathing base weakly strigose abaxially;

stipules absent;

petiole (1–)1.5–2.5(–3) cm, hairs abundant, ascending to spreading, 1–4 mm;

leaflets 15–25 per side, loosely overlapping, (1.5–)2–7 mm, lobes 0–4(–6), lanceolate or oblanceolate to elliptic, hairs abundant, spreading to ascending, 1–3 mm.

Cauline leaves

2–5.

Inflorescences

(7–)15–50-flowered, 2–8 cm diam., flowers arranged individually and/or in several to many loose few-flowered glomerules.

Pedicels

(3–)6–15(–22) mm.

Flowers

8–13 mm diam.;

epicalyx bractlets lanceolate to elliptic, 2–3 mm;

hypanthium patelliform to shallowly cupulate, 1.5–2.5 × 3–4.5 mm, ± 1/2 as deep as wide;

sepals often purple-suffused, 2.3–4(–5) mm, acute;

petals white, broadly spatulate or obovate to orbiculate, (2.8–)3–5(–6) mm;

stamens 20, filaments filiform, (1–)1.5–3 mm, anthers light pink, 0.3–0.5 mm;

carpels 8–20, styles 2.2–3 mm.

Achenes

light brown, 1.2–1.3 mm.

Ivesia pityocharis

Phenology

Flowering summer.

Habitat

Vernally saturated meadows, in sagebrush communities

Elevation

2100–2700 m (6900–8900 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.

Ivesia pityocharis is known only from the Pine Nut Mountains, Douglas County. Plants are somewhat intermediate between those of I. kingii and I. sericoleuca in having relatively shallow hypanthia and loosely sericeous vestiture. Hairs on petioles and stem bases of I. pityocharis are to 4 mm; those of I. kingii are 1 mm and generally appressed-ascending.

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

Source

FNA vol. 9, p. 242.

FNA vol. 9, p. 241.

Parent taxa

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

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

I. aperta, I. argyrocoma, 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. 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)

Ertter: Syst. Bot. 14: 241, fig. 6. (1989)

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).

Choose a data source: Flora of North America

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Flora of North America species comparison

Ivesia argyrocoma

Ivesia pityocharis

Ivesia argyrocoma

Ivesia pityocharis