Eupatorium leucolepis |
Eupatorium anomalum |
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justiceweed, white-bract thoroughwort |
Florida thoroughwort |
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Habit | Perennials, 40–100+ cm. | Perennials, 80–150+ cm. | ||||
Stems | (from short caudices or stout rhizomes) single, sparsely branched distally, puberulent throughout (more densely distally and among heads). |
(from tuberous rhizomes) single, densely branched distally (shoots often develop from lateral buds), puberulent throughout (denser distally). |
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Leaves | usually opposite (distal sometimes alternate, ascending to vertical); sessile; blades pinnately nerved, lance-oblong to linear-oblong, 20–60 × 4–10(–15) mm, bases rounded to cuneate (not connate-perfoliate), margins entire or serrate, apices acute, faces villous (abaxial), scabrous (adaxial), gland-dotted. |
usually opposite (distal sometimes alternate); sessile or subsessile; blades 3-nerved distal to bases, elliptic to oblong, 15–50 × (5–)10–20 mm, bases cuneate, margins entire or serrate (unevenly toothed), apices rounded to acute, faces puberulent (abaxial) or glabrate (adaxial), gland-dotted (both). |
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Florets | 5; corollas 3–3.5 mm. |
5; corollas 3–3.5 mm. |
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Phyllaries | 8–10 in 2–3 series, narrowly elliptic, 2.5–8 × 0.8–1.2 mm, acuminate to attenuate, mucronate, abaxial faces puberulent, gland-dotted. |
8–12 in 2–3 series, oblong to lanceolate, 2.5–5 × 0.5–0.7 mm, apices rounded to acute, abaxial faces puberulent throughout. |
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Heads | in corymbiform arrays. |
in corymbiform arrays. |
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Cypselae | 2–3 mm; pappi of 30–40 bristles 4.5–5 mm. |
1.8–3 mm; pappi of 20–35 bristles 3.5–4.5 mm. |
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2n | = 20, 30, 40. |
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Eupatorium leucolepis |
Eupatorium anomalum |
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Phenology | Flowering Jul–Aug. | |||||
Habitat | Wet, low ground, flatwoods | |||||
Elevation | 10–100 m (0–300 ft) | |||||
Distribution |
AL; DE; FL; GA; LA; MA; MD; MS; NC; NJ; NY; PA; RI; SC; TN; TX; VA
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AL; FL; GA; NC; SC |
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Discussion | Varieties 2 (2 in the flora). Eupatorium leucolepis is distinct morphologically by its acuminate to attenuate phyllaries, linear and usually plicate leaves, and phyllotaxy that is almost always strictly opposite to the arrays, with well-separated nodes. Eupatorium leucolepis has recently been shown to include two distinct species, an unnamed diploid that is endemic to Carolina Bay habitats and a series of relatively widespread and mostly polyploid, apomictic populations that include the type. It was recognized after preparation of this treatment that E. novae-angliae (E. leucolepis var. novae-angliae) was derived from hybridization between the unnamed diploid and E. perfoliatum, and is here recognized as a distinct species; it is not directly related genetically to E. leucolepis and thus is not appropriately classified as a variety of it. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Eupatorium anomalum has been proposed to be intermediate in morphology between E. rotundifolium and E. mohrii and, possibly, a hybrid derivative of that pairing. Molecular data suggest that its derivation is from hybridization between E. serotinum and E. mohrii. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 21, p. 469. | FNA vol. 21, p. 466. | ||||
Parent taxa | Asteraceae > tribe Eupatorieae > Eupatorium | Asteraceae > tribe Eupatorieae > Eupatorium | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | E. glaucescens var. leucolepis | |||||
Name authority | (de Candolle) Torrey & A. Gray: Fl. N. Amer. 2: 84. (1841) | Nash: Bull. Torrey Bot. Club 23: 106. (1896) | ||||
Web links |