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Dendrobium Sw.
石斛屬
Tufted epiphytic herbs. Stems terete, nodose, fleshy or not, erect or pendulous, often thickened and forming short pseudobulb, sometimes partly dilated into several pseudobulbs, mostly surrounded by tight, persistent sheaths. Leaves coriaceous or subcoriaceous, entire, flat or rarely subterete and laterally flattened, often articulate with sheaths. Inflorescence terminal or lateral, from nodes of stem, racemose or flower solitary, rarely cymose; peduncle obscure or shorter than pedicel; bracts minute. Flowers resupinate; sepals subequal, dorsal one free, lateral ones often oblique at base and adnate to foot of column and forming spur-like or saccate mentum; petals more or less similar to dorsal sepal; lip various, attached to and usually incumbent on foot of column, contracted or clawed at base, often 3-lobed; lateral lobes erect, embracing column; column short, with prominent foot; anther terminal, incumbent, 2celled; pollinia 4, ovoid or oblong, waxy, connate laterally in pairs in each cell, without caudicle or viscidium; rostellum usually hooked below. Capsules ovoid to oblong.
About 1,000 species, from Japan, Korea and China, through India, Malaysia and Indonesia to Papua New Guinea and Australia; 12 species in Taiwan.
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KEY TO SPECIES
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| 1 |
Stems fleshy, more than 5 mm in diam., usually thickened, or sometimes partly swollen and forming fusiform pseudobulbs. |
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(2) |
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Stems not fleshy, wire-like, slender, less than 2.5 mm in diam., without thickening or pseudobulb. |
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(10) |
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| 2 (1) |
Stems fleshy and thickened throughout their length; rarely partly dilated to form many fusiform pseudobulbs. |
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(3) |
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Stems swollen near base and forming pseudobulb of 1-3 internodes. |
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(9) |
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| 3 (2) |
Internodes usually cylindrical or clavate; mentum less than half length of pedicel. |
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(4) |
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Internodes usually obconic-cylindrical; mentum more than 3/4 length of or nearly as long as pedicel. |
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(8) |
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| 4 (3) |
Stems branched, each branch slender but developed discontinuously into many pseudobulbs with 2 or 3 internodes. |
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Dendrobium falconeri |
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Stems usually simple, uniformly fleshy or thickened throughout their length. |
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(5) |
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| 5 (4) |
Internodes clavate or sometimes obconic-cylindrical, ca. 1 cm in diam. |
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Dendrobium linawianum |
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Internodes usually cylindrical, less than 6 mm in diam. |
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(6) |
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| 6 (5) |
Stems usually yellowish; leaves 9-10 cm long; flowers yellow to orange; petals obovate. |
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Dendrobium aurantiacum |
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Stems greenish or sometimes purplish; leaves less than 7 cm long; petals ovate-oblong or oblong. |
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(7) |
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| 7 (6) |
Leaves lanceolate-linear; raceme with 1-4 white flowers. |
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Dendrobium moniliforme |
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Leaves ovate-lanceolate; raceme with 4-7 greenish yellow flowers. |
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Dendrobium tosaense |
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| 8 (3) |
Stems usually simple, erect or ascending; leaves 6-10 cm long, flowers blue violet. |
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Dendrobium miyakei |
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Stems branched, pendulous; leaves 3.5-5 cm long; flowers white. |
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Dendrobium chameleon |
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| 9 (2) |
Pseudobulbs with 2 or 3 internodes, more than 1.5 cm in diam.; leaves flat. |
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Dendrobium crumenatum |
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Pseudobulbs with 1 or 2 internodes, less than 8 mm in diam.; leaves subterete, fleshy. |
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Dendrobium equitans |
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| 10 (1) |
Stems erect, rigid, straight; inflorescence a 2-flowerd cyme; lip usually 3-lobed. |
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(11) |
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Stems suberect, often curved or slightly pendulous near apex; flowers few in short raceme; lip nearly undivided. |
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Dendrobium leptocladum |
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| 11 (10) |
Leaves ca. 11 cm long; perianth 3 cm long; lip with pilose disc. |
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Dendrobium furcatopedicellatum |
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Leaves 7 cm long; perianth 2 cm long; lip with glabrous disc bearing 3 fimbriate keels. |
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Dendrobium somai |
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List of lower taxa
| Related Links (opens in a new window) |
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Treatments in Other Floras @ www.efloras.org
Other Databases
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