treatments/ELEPHANTOPUS

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ELEPHANTOPUS Elephantopus Linnaeus Sp. Pl.. 2: 814. 1753.

Elephant’s foot [Greek elephantos , elephant, and pous , foot; probably alluding to rosettes of basal leaves in original species]

John L. Strother,

Perennials, (1–)2–8(–12+) dm; often rhizomatous or stoloniferous. Leaves mostly basal or mostly cauline at flowering; sessile or petiolate, petioles ± winged (often clasping at bases); blades mostly elliptic, ovate, or obovate to lanceolate, oblanceolate, or spatulate (rarely orbiculate), bases ± cuneate, margins usually toothed (rarely entire), apices obtuse to acute, abaxial or both faces usually resin-gland-dotted. Heads ± discoid, sessile, not individually bracteate, in clusters of (1–)10–40+ in corymbiform-paniculiform arrays 6–15(–25) cm diam. (each cluster subtended by 2–3 ± deltate bracts). Involucres ± cylindric, 1–3+ mm diam. Phyllaries 8 in 4 decussate pairs, the outer 4 ovate, inner 4 lanceolate, all ± chartaceous, margins entire, tips ± spinose to apiculate, abaxial faces of inner 4 usually dotted distally with resin glands. Florets (1–)4(–5+); corollas white or pink to purple, tubes longer than abruptly funnelform throats, lobes 5, lance-linear, unequal (abaxial sinus deepest). Cypselae ± clavate, sometimes ± flattened, 10-nerved or -ribbed, strigillose to hirsutulous; pappi persistent, of 5(–6), 1-aristate scales (look closely for squamiform, gradually to abruptly tapering base of each arista). x = 11.


Species 12–15+ (4 in the flora):mostly warm-temperate; subtropical; and tropical regions worldwide; sometimes as naturalized ruderals.;

Pseudelephantopus spicatus is sometimes treated as a member of Elephantopus.
SELECTED REFERENCES
Clonts, J. A. 1972. A Revision of the Genus Elephantopus Including Orthopappus and Pseudelephantopus (Compositae). Ph.D. thesis. Mississippi State University.


1. Leaves at flowering all or mostly cauline 1. Elephantopus carolinianus
1. Leaves at flowering mostly basal (cauline leaves much smaller or wanting). (2.)
2. Inner phyllaries 9–11+ mm; pappi 6–8 mm 2. Elephantopus tomentosus
2. Inner phyllaries 6–8 mm; pappi 3–4.5 mm. (3.)
3. Inner phyllaries ± densely strigose-villous with hairs (0.3–)0.5–1 mm; cypselae 3– 3.5 mm 3. Elephantopus elatus
3. Inner phyllaries sparsely strigose or hispidulous with hairs 0.05–0.3(–0.5) mm; cypselae 2.5–3 mm 4. Elephantopus nudatus