Viguiera dentata |
Viguiera |
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sunflower goldeneye, toothleaf, toothleaf goldeneye |
goldeneye |
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Habit | Perennials, 100–200 cm. | Perennials or shrubs [annuals], 50–200 cm. | ||||||||
Stems | erect or ascending, unbranched or branched. |
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Leaves | opposite (proximal) or alternate (distal); petioles 10–55 mm; blades ovate or rhombic-ovate to lance-ovate or lanceolate, 3.5–12.5 × 1–8 cm, margins serrate or serrulate, faces strigose. |
mostly cauline; opposite (proximal) and/or alternate (distal); petiolate or ± sessile; blades often 3-nerved (from at or near bases), deltate, deltate-ovate, lance-linear, lanceolate, lance-ovate, linear, linear-filiform, rhombic-ovate, or ovate, sometimes pinnately lobed, ultimate margins entire or toothed, faces glabrous or hairy, often gland-dotted. |
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Peduncles | 3–14 cm. |
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Involucres | 11–18 × 7–10 mm. |
hemispheric [campanulate], (5–18 ×) 7–15 mm. |
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Receptacles | flat to convex, paleate (paleae tan, conduplicate, apices often 3-lobed or -toothed). |
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Ray florets | 10–14; tubes 1 mm, laminae 7–15 mm. |
6–18, neuter; corollas yellow (laminae 2–4-lobed). |
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Disc florets | 50+; corollas 3–4 mm (staminal filaments hairy). |
40–100+, bisexual, fertile; corollas yellow, tubes shorter than campanulate throats, lobes 5, triangular (style branches slender, apices acute or attenuate). |
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Phyllaries | persistent, 10–30 in 2–5 series (subequal to unequal). |
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Heads | usually 3–9+ in ± corymbiform arrays. |
radiate, borne singly or (2–25+) in open to crowded, ± corymbiform arrays. |
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Cypselae | 3.5–3.8 mm, ± strigose; pappi of 2 lacerate, aristate scales 2.2–2.8 mm plus 2–4 lacerate scales 0.5–0.7 mm. |
(purplish black, often mottled) ± compressed, often obpyramidal (usually strigose, sometimes glabrous); pappi 0, or persistent or tardily falling, of 2 lacerate, aristate scales (2.2–5.5 mm) plus [0–]2–4[–6] lacerate or aristate scales (0.5–1.3 mm). |
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Phyllary | apices abruptly narrowed to acuminate or spatulate (phyllary bases broad, indurate, apices herbaceous). |
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Paleae | 6.5 mm, apices prominently cuspidate. |
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x | = 17. |
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2n | = 34. |
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Viguiera dentata |
Viguiera |
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Phenology | Flowering Jun–Oct. | |||||||||
Habitat | Dry slopes and canyons, fields, roadside ditches | |||||||||
Elevation | 100–2300 m (300–7500 ft) | |||||||||
Distribution |
AZ; NM; TX; Mexico; Central America; West Indies (Cuba)
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sw United States; Mexico; Central America; South America |
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Discussion | Viguiera dentata is widespread and variable. It is unique in Helianthinae in the hairy staminal filaments. The name V. dentata var. lancifolia S. F. Blake has been used for plants from Mexico. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Species ca. 150 (3 in the flora). Viguiera has been long recognized as paraphyletic. Molecular studies are helping to clarify its phylogeny, and the corresponding systematic adjustments are beginning (E. E. Schilling and J. L. Panero 2002). Some groups have already been separated, including Bahiopsis and Heliomeris. It is likely that the genus will be narrowed to include only a single species, V. dentata (including V. helianthoides Kunth), and that new or resurrected genera will accommodate the remaining species. As currently circumscribed, the genus occurs primarily in Mexico and South America and reaches its northern limit of distribution in the southwestern United States. The Mexican (Chihuahua, Durango) V. phenax was collected a single time in Texas [where it was named Helianthus ludens Shinners and Viguiera ludens (Shinners) M. C. Johnston]; it apparently has not become established in the flora area. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 21, p. 173. | FNA vol. 21, p. 172. | ||||||||
Parent taxa | Asteraceae > tribe Heliantheae > subtribe Helianthinae > Viguiera | Asteraceae > tribe Heliantheae > subtribe Helianthinae | ||||||||
Sibling taxa | ||||||||||
Subordinate taxa | ||||||||||
Synonyms | Helianthus dentatus | |||||||||
Name authority | (Cavanilles) Sprengel: Syst. Veg. 3: 615. (1826) | Kunth: in A. von Humboldt et al., Nov. Gen. Sp. 4(fol.): 176. (1818) | ||||||||
Web links |