Contains 3 accepted taxa overall.
Characteristics
Classification
Citation
DIOSCOREA Linnaeus, Sp. Pl. 1032. 1753, nom. cons. propos.
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TYPE: Dioscorea sativa Linnaeus, typ. cons. propos. Lectotypified by Britton & A. Brown, Ill. Fl. N. U.S., ed. 2. 1: 535. 1913.
Species
| Scientific Name | Common Name | Herbarium Specimens | Status | Photos |
|---|---|---|---|---|
| Dioscorea floridana | Florida Wild Yam | |||
| Dioscorea polystachya | Cinnamon Vine, Chinese Yam | |||
| Dioscorea villosa | Wild Yam |
Identification Key
1. Leaf blade upper surface variegated whitish along the midrib, the lower surface pale green to purplish
1. Leaf blade upper surface not variegated, the lower surface green or glaucous
2
2. Plants rhizomatous; bulbils never produced in leaf axils; leaf margins entire or repand; petiole base never clasping; inflorescences regularly produced
3
2. Plants tuberous; bulbils produced in leaf axils; leaf margins lobed or entire; petiole base sometimes clasping; inflorescences absent or infrequent, or often only one sex present
4
3. Rhizomes yellow, nodes articulate, each bearing 1 dark, contrasting, somewhat deltate scale leaf or the dark vertical scar remaining once leaf falls; staminate inflorescences (1)2–5 in leaf axils; perianth of both staminate and pistillate flowers yellow to orangish yellow; stamens inwardly curved; thecae connate
3. Rhizomes brownish, nodes not articulate; staminate inflorescences solitary in leaf axils; perianth of both staminate and pistillate flowers greenish white; stamens erect; thecae distinct, widely spreading
4. Leaf blade unlobed
5
4. Leaf blades lobed, with a sinus, sometimes obscure
6
5. Stems broadly winged, 4-angular; leaves often opposite or subopposite, the blade base margin somewhat straight and sagittate and angled; seeds winged all around
5. Stems terete, usually unwinged; leaves alternate throughout, the blade base mostly evenly rounded; seeds unilaterally winged
6. Leaf blade hastate-cordate, margins 3-lobed, lobes rounded, blade apex acute or mucronate; petiole base not clasping
6. Leaf blade reniform, margins irregularly 3-5-lobed, lobes often elongate or acuminate, blade apex conspicuously caudate
Genus Synonyms
| Synonym | Full Citation | Basionym | Type |
|---|---|---|---|
| No synonyms found. | |||