Chorizanthe diffusa |
Chorizanthe obovata |
|
---|---|---|
diffuse spineflower |
spoon-sepal spineflower |
|
Habit | Plants spreading, decumbent, prostrate, or rarely slightly erect, 0.3–1(–1.5) × 0.5–2(–10) dm, villous. | Plants erect to prostrate, (0.5–)1–3(–4) × 1–4(–5) dm, pubescent. |
Leaves | basal; petiole 0.2–1.8(–2) cm; blade oblanceolate, 0.3–2 × 0.1–0.4 cm, villous. |
basal; petiole 0.5–2(–3) cm; blade oblanceolate, 0.5–2.5 × 0.3–1 cm, thinly pubescent adaxially, soft-hirsute abaxially. |
Inflorescences | rather dense with secondary branches suppressed, white to greenish; bracts 2, similar to leaf blades at proximal nodes only reduced, short-petiolate, becoming linear and aciculate at distal nodes, acerose, 0.3–2 cm × 1–4 mm, awns absent. |
with involucres in open clusters 2–4(–6) cm diam., greenish or reddish; bracts 2–3 at proximal node, usually leaflike, without whorl of sessile bracts about midstem, elliptic, 0.5–1.5 cm × 2–6(–8) mm, abruptly reduced above proximal node, becoming scalelike, linear, aciculate, acerose, 0.2–1 cm × 1–3 mm, awns straight, 1–2 mm. |
Involucres | 1, mostly greenish, cylindric, not ventricose, 2–2.5 mm, with thin to broad and then conspicuous white or pinkish to purple, scarious margins extending nearly full length of awn, not corrugate, villous-hirsute; teeth spreading to divergent, equal, 0.5–1 mm, awns uncinate with longer ones 1–2 mm, anterior one mostly 2 mm, alternating with shorter (0.5–1 mm) ones. |
3–10+, grayish, urceolate, slightly ventricose basally, 3–4 mm, slightly corrugate, without scarious or membranous margins, thinly to densely pubescent; teeth erect to spreading, unequal, 1–2 mm; awns straight or uncinate with longer anterior one straight, mostly 1 mm, others uncinate, 0.5–1 mm. |
Flowers | exserted; perianth bicolored with floral tube lemon-yellow and tepals white, campanulate, 2.5–3 mm, glabrous; tepals connate ca. 1/3 their length, monomorphic, oblong, acute to obtuse and entire apically; stamens 3–9, slightly exserted; filaments distinct, 1.5–2 mm, glabrous; anthers yellow, oval, 0.3–0.4 mm. |
exserted; perianth bicolored with floral tube greenish white to white and tepals white to pink, cylindric, 4–4.5(–5) mm, sparsely pubescent; tepals connate 1/2 their length, dimorphic, obovate, those of outer whorl spreading, 2 times longer than those of inner whorl, rounded or slightly obcordate apically, those of inner whorl erect, narrower, fimbriate apically; stamens (6–)9, mostly included; filaments distinct, 4–4.5 mm, glabrous; anthers yellow to golden, oblong, 0.9–1.1 mm. |
Achenes | dark brown, globose-lenticular, 2–2.5 mm. |
brown, globose-lenticular, 3–3.5 mm. |
2n | = 38, 40, 42. |
= 38, 40, 42. |
Chorizanthe diffusa |
Chorizanthe obovata |
|
Phenology | Flowering Apr–Jul. | Flowering May–Jul. |
Habitat | Sandy to gravelly flats and slopes, coastal scrub communities, pine-oak woodlands | Sandy or calcareous soils, mixed grassland, coastal scrub, or chaparral communities, pine-oak woodlands |
Elevation | 30-800 m (100-2600 ft) | 10-1300 m (0-4300 ft) |
Distribution |
CA
|
CA
|
Discussion | The involucral margins of Chorizanthe diffusa vary greatly. In some individuals, the white margins are barely visible. Plants with the margins of the involucre are predominantly white have been designated var. nivea. A full gradation between the extremes may be observed in most populations, although in coastal sands var. nivea is often the dominant expression. Diffuse spineflower occurs near the coast and in the Coast Ranges of central California. Chorizanthe diffusa has been shown to inhibit carcinogen-induced preneoplastic lesions in a mouse mammary-organ culture model. This inhibitory activity is known to correlate with cancer chemopreventive effects in full-term models of tumorigenesis (see H. S. Chung et al. 1999). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Chorizanthe obovata is found in the Coast Ranges. The whitish flowers quickly distinguish it from C. palmeri and the other reddish-flowered members of this complex. Immature plants can be confused with C. staticoides; the floral features readily separate the two species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 5, p. 452. | FNA vol. 5, p. 459. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | C. andersonii, C. diffusa var. nivea, C. nivea, C. pungens var. diffusa, C. pungens var. nivea | |
Name authority | Bentham: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 14: 26. (1856) | Goodman: Ann. Missouri Bot. Gard. 21: 70. (1934) |
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