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Senecio L.
黃菀屬
PENG, Ching-I & CHUNG, Shih-Wen
Annual or perennial herbs, subshrubs, shrubs or small trees, generally with alternate leaves, very variable in habit and foliage. Heads radiate or discoid. Involucre generally calyculate. Florets mostly yellow, sometimes pink, purple, or violet, only rarely white. Anthers not caudate; filament collar dilated. Style branches truncate to obtuse, with a crown of hairs, without appendage, with discrete stigmatic lines. Achenes ellipsoid-obovoid, ribbed, glabrous or pubescent, sometimes with myxogenic hairs.
Pappus of many fine bristles.
Worldwide but most species in South America (ca. 500 species) and Africa (ca. 350 species), some widespread weedy species, in total ca. 1,250 species; in Taiwan, about seven species, one of which is represented by two varieties.
- Jeffrey, C. & Y. L. Chen. 1984. Taxonomic studies on the tribe Senecioneae (Compositae) of Eastern Asia. Kew. Bull. 39(2): 205-446.
- Koyama, H. 1969. Taxonomic studies on the tribe Senecioneae of eastern Asia. II. Enumeration of the species of the species eastern Asia. Mem. Fac. Sci. Kyoto Univ., Ser. Biol. 2(2): 137-183.
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KEY TO SPECIES
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| 1 |
Plants annual with fibrous roots; heads discoid. |
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Senecio vulgaris |
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Plants perennial with rootstocks; heads radiate. |
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(2) |
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| 2 (1) |
Leaves mainly radical, rosulate, persistent at anthesis; flowering stems scape-like, with bracteate leaves. |
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Senecio taitungensis |
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Leaves cauline, radical leaves usually withered at anthesis; flowering stems terminal and/or axillary; heads not on a scape-like flowering stem. |
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(3) |
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| 3 (2) |
Leaves thick chartaceous, petiole 3-8 cm long; peduncle 2.5-6(-12) cm long; ray florets 8-12. |
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Senecio tarokoensis |
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Leaves chartaceous, petiole 0-2 cm long; peduncle 0.5-2(-3) cm long; ray florets 5-8. |
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(4) |
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| 4 (3) |
Stems erect; leaves linear, elliptic to oblong-lanceolate. |
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(5) |
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Stems weakly erect, ascending, or scandent; leaves triangular or narrowly so. |
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(6) |
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| 5 (4) |
Leaves bipinnately, pinnately, lyrately or runcinately lobed. |
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Senecio morrisonensis |
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Leaves dentate. |
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var. dentatus |
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| 6 (4) |
Stems weakly erect, ascending to nearly scandent, 10-60 cm tall; leaves usually thick chartaceous, 1-4 cm long; heads (1-)3-10 in lax corymbs at apex of stems and branches. |
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Senecio crataegifolius |
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Stems scandent, 2-5 m tall; leaves chartaceous, 4-10 cm long; heads many, in large axillary paniculate corymbs. |
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(7) |
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| 7 (6) |
Leaves subentire to dentate, unlobed and without small lateral lobes at base. |
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var. scandens |
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Leaves pinnatifid, or with a large terminal lobe and several lateral lobes at base. |
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var. incisus |
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Lower Taxa
Related Synonym(s):
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