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chamise horkelia, Parry horkelia, Parry's horkelia

Santa Rosa, Santa Rosa horkelia, Sonoma horkelia, thin-lobed, thin-lobed horkelia

Habit Plants forming open mats. Plants loosely matted, green.
Stems

ascending to erect, 1–3(–3.5) dm.

ascending to erect, 1–4 dm, hairs ± spreading.

Basal leaves

4–10(–12) × 1–2 cm;

leaflets 3–6(or 7) per side, narrowly obovate, 5–12(–15) × 4–8(–10) mm, 1/2–3/4 as wide as long, divided ± 1/4 to midrib into 5–10 oblong to broadly obovate teeth, sparsely pilose especially on midveins and margins.

weakly planar to ± cylindric, 5–15(–20) × 0.5–1.5 cm;

stipules entire;

leaflets 8–16(–20) per side, ± overlapping especially distally, cuneate to flabellate, 3–10 × 2–10 mm, 1/2 to nearly as wide as long, divided 1/2–3/4+ to midrib into 3–8 linear to narrowly oblanceolate or narrowly elliptic lobes, sparsely villous at least marginally, often with a tuft of hairs apically.

Cauline leaves

1–4.

2–5.

Inflorescences

open to congested, flowers arranged individually and in glomerules, these sometimes subcapitate.

Pedicels

(3–)5–15 mm.

1–6 mm.

Flowers

15 mm diam.;

epicalyx bractlets linear-lanceolate to narrowly elliptic, 2–5 × 0.5–1.5 mm, ± 2/3 length of sepals;

hypanthium 0.6–1 × 2.5–4 mm, less than 1/3 as deep as wide;

sepals ± spreading to reflexed, lanceolate to narrowly elliptic, 3.5–6 mm;

petals elliptic to obovate, 4–7 × 3 mm, apex obtuse to rounded to truncate or slightly emarginate;

filaments 1–3 × 0.6–1.3 mm, anthers 0.6–1 mm;

carpels (17–)20–50;

styles 1.5–2.5 mm.

10 mm diam.;

epicalyx bractlets narrowly to broadly lanceolate, 1–3 × 0.5–1 mm, slightly shorter than sepals, entire;

hypanthium 1–1.2 × 2.5–4.5 mm, less than 1/2 as deep as wide, interior pilose;

sepals spreading to reflexed, lanceolate, 3–5 mm;

petals oblanceolate, 2.5–4.5 × 1.5 mm, apex emarginate;

filaments (1–)1.5–2 × 0.5 mm, anthers 0.4–0.6 mm;

carpels 10–25;

styles 1.8–2.2 mm.

Achenes

grayish, 1.3–1.5 mm, finely reticulate.

light brown, 1.5 mm, smooth or slightly rugose.

2n

= 28.

= 28.

Horkelia parryi

Horkelia tenuiloba

Phenology Flowering late spring–early summer. Flowering summer.
Habitat Chaparral, pine-oak woodlands, primarily on Ione Formation, rarely on schist or limestone Sandy soil, openings, in chaparral, oak woodlands
Elevation 80–900 m (300–3000 ft) 50–500 m (200–1600 ft)
Distribution
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
Discussion

Of conservation concern.

Horkelia parryi is known from the foothills of the western Sierra Nevada in Amador, Calaveras, and El Dorado counties, and is disjunct in Mariposa County.

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

Of conservation concern.

Horkelia tenuiloba occurs on the western edges of the northern Coast Ranges in Marin, Mendocino, and Sonoma counties. Populations from San Luis Obispo formerly included in this species now are part of H. yadonii. A specimen (M. K. C[urran], July 5, 1885, UC) unequivocally of H. tenuiloba purportedly from San Luis Obispo is in all likelihood mislabeled with respect to locality.

Horkelia tenuiloba is commonly associated with seral openings in chaparral and woodlands and might be dependent on periodic disturbance by fire.

W. L. Jepson (1909–1943, vol. 2) used Potentilla stenoloba (1895) for the species encompassing the types of Horkelia tenuiloba and P. micheneri. The epithet micheneri (1893) has priority at species rank within Potentilla, since P. tenuiloba (Torrey) Greene is a later homonym of P. tenuiloba Jordan.

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

Source FNA vol. 9, p. 258. FNA vol. 9, p. 252.
Parent taxa Rosaceae > subfam. Rosoideae > tribe Potentilleae > Horkelia > sect. Parryae Rosaceae > subfam. Rosoideae > tribe Potentilleae > Horkelia > sect. Horkelia
Sibling taxa
H. bolanderi, H. californica, H. clevelandii, H. congesta, H. cuneata, H. daucifolia, H. fusca, H. hendersonii, H. hispidula, H. howellii, H. marinensis, H. rydbergii, H. sericata, H. tenuiloba, H. tridentata, H. truncata, H. tularensis, H. wilderae, H. yadonii
H. bolanderi, H. californica, H. clevelandii, H. congesta, H. cuneata, H. daucifolia, H. fusca, H. hendersonii, H. hispidula, H. howellii, H. marinensis, H. parryi, H. rydbergii, H. sericata, H. tridentata, H. truncata, H. tularensis, H. wilderae, H. yadonii
Synonyms Potentilla parryi H. fusca var. tenuiloba, Potentilla micheneri, P. stenoloba
Name authority Greene: Bull. Calif. Acad. Sci. 2: 416. (1887) (Torrey) A. Gray: Proc. Amer. Acad. Arts 6: 529. (1865)
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