The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Douglas' spineflower, San Benito spineflower

devil's spineflower, rigid spineflower, rigid spiny-herb, spiny-herb

Habit Plants erect, 1–4(–5) × 0.5–3 dm, villous. Plants erect, 0.2–0.8(–1.5) × 0.1–0.7(–1) dm, pubescent.
Leaves

basal;

petiole 1–3(–6) cm;

blade oblanceolate, 0.5–2(–4) × 0.1–0.4(–1) cm, villous.

basal and cauline;

petiole 0.5–3(–4) cm;

basal blade broadly elliptic to obovate, 0.5–2.5 × (0.3–)0.5–2 cm, thinly pubescent adaxially, more densely so to tomentose abaxially;

proximal cauline leaf soon deciduous, 1, blade similar to basal leaf blades only 1–2(–2.5) × 0.5–1.5 cm, mucronate to awn-tipped, awn mostly 2–4 mm;

distal cauline leaf blade persistent, 1 per node, sessile, blade linear to linear-lanceolate, 0.1–1.5 × 0.05–0.15 cm, becoming hard and thornlike with age.

Inflorescences

cymose, dichotomously branched throughout, white to greenish or reddish;

bracts usually 2, similar to proximal leaf blades, typically with whorl of 3–5 ca. midstem, short-petiolate, becoming linear and aciculate at distal nodes, acerose, 0.5–2(–3) cm × 1–5(–10) mm, awns absent.

with involucres in dense clusters in axils of bracts, these on short shoots and each subtended by cauline leaves;

bracts 2, subopposite to opposite, linear, 0.5–1(–1.2) cm × 1–2 mm, awns straight, 2–4 mm.

Involucres

congested in small leafy terminal clusters of 2–4 at nodes of dichotomies, greenish, cylindric, slightly ventricose basally, 3–5 mm, with conspicuous, purple, broad, membranous margins typically extending across sinuses, finely corrugated, hispid at least along ridges, otherwise sparsely pubescent;

teeth spreading, equal, (0.7–)1–1.5 mm, awns straight, 0.5–1 mm.

1, greenish, urceolate, 3-ribbed, 2–3 mm, corrugate, pubescent, rarely villous near base in some;

teeth 3, unequal, with thickened anterior tooth toward base, 5–10 mm, sometimes expanding and becoming lanceolate to narrowly elliptic, others 0.5–1.2 mm;

awns straight.

Flowers

exserted;

perianth white to rose, cylindric, 3.5–4(–4.5) mm, slightly pubescent abaxially;

tepals connate 2/3 their length, monomorphic, obovate, 2-lobed or denticulate apically, infrequently inner whorl entire;

stamens 9, slightly exserted;

filaments distinct, 3–4 mm, glabrous;

anthers pink to red, oblong, 0.5–0.6 mm.

1–2, included to slightly exserted;

perianth yellow, cylindric, 1.5–1.8 mm, densely pubescent abaxially;

tepals connate ca. 2/3 their length, monomorphic, oblong, rounded, entire apically;

stamens 9, slightly exserted;

filaments distinct, 0.5–1 mm, glabrous;

anthers yellowish, ovate, 0.2–0.3 mm.

Achenes

light brown, globose-lenticular, 3.5–4 mm.

brown, 3-gonous, (1.5–)1.8–2.2 mm.

2n

= 40.

= 38, 40.

Chorizanthe douglasii

Chorizanthe rigida

Phenology Flowering Apr–Jul. Flowering Feb–Jun.
Habitat Sandy to gravelly flats and slopes, mixed grassland communities, oak and pine woodlands Sandy to gravelly or rocky flats and slopes, desert scrub
Elevation (200-)300-1600 m ((700-)1000-5200 ft) -60-1900 m. (-200-6200 ft.)
Distribution
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CA; NV; UT; Mexico (Baja California, Sonora)
[WildflowerSearch map]
[BONAP county map]
Discussion

Chorizanthe douglasii is restricted to the Santa Lucia Mountains and to the San Gabilan and La Panza ranges of west-central California. The species is infrequent but can be locally common. A single collection made in the Santa Cruz Mountains (Rowntree s.n., 16 Jun 1929, CAS) may have been made in Santa Cruz County, but the location is uncertain and no other collection is known from that region.

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

Anyone with the misfortune to step bare-footed on Chorizanthe rigida after the plant has dried instantly appreciates its common name. The species is widespread on the Mojave and Sonoran deserts but only occasionally is it locally abundant or weedy. It is found also along the Lahontan Trough in western Nevada, a well-known biogeographic extension route north of the Mojave Desert (J. L. Reveal 1980). The exceedingly compact and dense inflorescences with suppressed secondary branches result in a series of leaves and bracts that subtend a closely arranged series of bracteated and involucrated flowers.

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

Source FNA vol. 5, p. 452. FNA vol. 5, p. 467.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Chorizanthe > subg. Amphietes > sect. Ptelosepala Polygonaceae > subfam. Eriogonoideae > Chorizanthe > subg. Amphietes > sect. Acanthogonum
Sibling taxa
C. angustifolia, C. biloba, C. blakleyi, C. brevicornu, C. breweri, C. clevelandii, C. corrugata, C. cuspidata, C. diffusa, C. fimbriata, C. howellii, C. leptotheca, C. membranacea, C. obovata, C. orcuttiana, C. palmeri, C. parryi, C. polygonoides, C. procumbens, C. pungens, C. rectispina, C. rigida, C. robusta, C. spinosa, C. staticoides, C. stellulata, C. uniaristata, C. valida, C. ventricosa, C. watsonii, C. wheeleri, C. xanti
C. angustifolia, C. biloba, C. blakleyi, C. brevicornu, C. breweri, C. clevelandii, C. corrugata, C. cuspidata, C. diffusa, C. douglasii, C. fimbriata, C. howellii, C. leptotheca, C. membranacea, C. obovata, C. orcuttiana, C. palmeri, C. parryi, C. polygonoides, C. procumbens, C. pungens, C. rectispina, C. robusta, C. spinosa, C. staticoides, C. stellulata, C. uniaristata, C. valida, C. ventricosa, C. watsonii, C. wheeleri, C. xanti
Synonyms C. nortonii Acanthogonum rigidum
Name authority Bentham: Trans. Linn. Soc. London 17: 418. (1836) (Torrey) Torrey & A. Gray: Proc. Amer. Acad. Arts 8: 198. (1870)
Web links