Malacothrix saxatilis |
Malacothrix fendleri |
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cliff aster, cliff desert dandelion |
Fendler's desert dandelion |
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Habit | Perennials (sometimes flowering first year), (20–)90–200 cm. | Annuals, 3–15(–25+) cm. | ||||||||||||||||
Stems | 1 (from rhizomes) or 2–3+ (from caudices), usually erect (sometimes relatively thick), branched mostly distally (usually relatively leafy proximally, sometimes sparsely leafy distally), glabrous or sparsely arachnose to tomentose. |
(1–)3–8, ± decumbent or spreading-ascending, branched proximally and distally, glaucous or glabrous. |
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Cauline leaves | proximal (somewhat thick, usually withering early) elliptic, oblanceolate, lanceolate, or linear (sometimes 1–2-pinnately lobed, lobes lanceolate or linear to filiform, sometimes antrorse, bases usually tapering), ultimate margins entire or dentate to denticulate, faces glabrous or ± arachnose to tomentose; distal reduced. |
proximal elliptic to oblong-oblanceolate, sometimes pinnately lobed (lobes 2–4+ pairs, oblong to triangular, unequal, apices acute), not fleshy, ultimate margins usually dentate, faces glabrous; distal reduced (narrowly triangular to linear or filiform, margins dentate or entire). |
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Involucres | ± campanulate, 9–12(–16+) × 6–8(–12+) mm. |
± campanulate, 7–10 × 5–6+ mm. |
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Receptacles | not bristly. |
not bristly. |
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Florets | 41–100; corollas white (usually each with abaxial purple stripe), 13–20 mm; outer ligules exserted 8–14 mm. |
16–88; corollas yellow (usually with red or purplish abaxial stripes), 6–14 mm; outer ligules exserted 5–8 mm. |
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Phyllaries | 18–30+ in 2–3 series, lanceolate or linear to subulate, hyaline margins 0.05–0.2 mm wide, faces glabrous or ± arachnose and glabrescent. |
13–25+ in 2–3 series, lance-oblong or lanceolate to lance-linear, subequal, hyaline margins 0.05–0.3 mm wide, faces glabrous. |
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Calyculi | of 12–18(–30), lanceolate to subulate bractlets, hyaline margins 0.05–0.2 mm. |
of 5–12, ovate to lanceolate bractlets, hyaline margins 0.05–0.2 mm wide. |
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Cypselae | ± prismatic, 1.4–2.5 mm, ribs extending to apices (± muriculate at 30x), 5 more prominent than others; pappi persistent, of fimbriate crowns or 20–25, blunt teeth (0.01–0.1 mm). |
± cylindric, 1.8–2.4 mm (distal 0.3 mm slightly expanded, cupped, smooth), ribs not extending to apices, ± equal; persistent pappi of 12–15, ± deltate teeth (often hidden within cups at apices of cypselae) plus 1–2 bristles. |
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Pollen | 70–100% 3-porate. |
70–100% 3-porate. |
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2n | = 18. |
= 14. |
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Malacothrix saxatilis |
Malacothrix fendleri |
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Phenology | Flowering Mar–Jun. | |||||||||||||||||
Habitat | Grasslands, pinyon-juniper woodlands, creosote bush associations | |||||||||||||||||
Elevation | 80–2200 m (300–7200 ft) | |||||||||||||||||
Distribution |
CA
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AZ; NM; TX; Mexico (Baja California, Sonora)
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Discussion | Varieties 5 (5 in the flora). The Malacothrix saxatilis complex is taxonomically difficult. The varieties intergrade morphologically in leaf shape, indument, blooming time, and growth cycle, depending on relative habitat conditions such as elevation, soil, and temperature regime. Hybridization may occur between varieties where they are sympatric. In addition, arrays of heads in early bloom may be described as congested (peduncles relatively short) and as open (peduncles relatively long) on the same plant at the end of the season. Varieties commutata, arachnoidea, and saxatilis are similar in leaf morphology; var. arachnoidea is distinguished from var. commutata mainly by its tomentose herbage; var. saxatilis differs from the other two varieties in minor details of leaf morphology and in its area of distribution; var. implicata is the most distinctive variety; and var. tenuifolia differs from the others primarily in cauline leaf morphology, which is quite variable. Variety altissima has been described as similar to vars. arachnoidea and commutata and different from vars. saxatilis, implicata, and tenuifolia in growth habit. It is similar in leaf morphology to var. tenuifolia but differs from vars. arachnoidea, commutata, implicata, and saxatilis. Here, var. altissima is subsumed in var. tenuifolia. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Malacothrix fendleri grows in the Sonoran Desert. “San Bernardino Co.” as locality for a specimen from the herbarium of J. G. Lemmon in UC (336493) is evidently an error. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 19, p. 318. | FNA vol. 19, p. 314. | ||||||||||||||||
Parent taxa | Asteraceae > tribe Cichorieae > Malacothrix | Asteraceae > tribe Cichorieae > Malacothrix | ||||||||||||||||
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Synonyms | Leucoseris saxatilis | |||||||||||||||||
Name authority | (Nuttall) Torrey & A. Gray: Fl. N. Amer. 2: 486. (1843) | A. Gray: Smithsonian Contr. Knowl. 5(6): 104. (1853) | ||||||||||||||||
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