Contains 7 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 alata | WHITE YAM | Not Native Y | ||
| Dioscorea bulbifera | AIR-POTATO | Not Native Y | ||
| Dioscorea dodecaneura | ORNAMENTAL YAM | Not Native | ||
| Dioscorea floridana | FLORIDA YAM | Native FAC (NWPL) | ||
| Dioscorea polystachya | CHINESE YAM; CINNAMON VINE | Not Native | ||
| Dioscorea sansibarensis | ZANZIBAR YAM | Not Native | ||
| Dioscorea villosa | WILD YAM; FOURLEAF YAM | Native FACW (NWPL) |
[Family 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 |
|---|---|---|---|
| Borderea | Borderea Miégeville, Bull. Soc. Bot. France 13: 374. 1866. | TYPE: Borderea pyrenaica Miégeville | |
| Botryosicyos | Botryosicyos Hochstetter, Flora 27(1, Bes. Beil.): 3. 1844. | TYPE: Botryosicyos pentaphyllus Hochstetter | |
| Elephantodon | Elephantodon Salisbury, Gen. Pl. 12. 1866. | TYPE: Dioscorea eburnea Loureiro | |
| Epipetrum | Epipetrum Philippi, Linnaea 33: 253. 1864. | TYPE: Epipetrum humile (Bertero & Colla) Philippi (Dioscorea humilis Bertero & Colla) | |
| Hamatris | Hamatris Salisbury, Gen. Pl. 11. 1866. | TYPE: Dioscorea triphylla Linnaeus | |
| Helmia | Helmia Kunth, Enum. Pl. 5: 414. 1850; Abh. Koenigl. Akad. Wiss. Berlin 1848: 55. 1850. | TYPE: Helmia dregeana Kunth Lectotypified by Caddick et al., Taxon 51: 108. 2002. | |
| Higinbothamia | Higinbothamia Uline, Publ. Field Columb. Mus., Bot. Ser. 1: 414, t. 22. 1899. | TYPE: Higinbothamia synandra Uline | |
| Merione | Merione Salisbury, Gen. Pl. 12. 1866. | TYPE: Dioscorea villosa Linnaeus | |
| Nanarepenta | Nanarepenta Matuda, Anales Inst. Biol. Univ. Mexico 32: 143. 1962. | TYPE: Nanarepenta tolucana Matuda | |
| Oncus | Oncus Loureiro, Fl. Cochinch. 190, 194. 1790. | TYPE: Oncus esculentus Loureiro | |
| Peripetasma | Peripetasma Ridley, J. Bot. 58: 147. 1920. | TYPE: Peripetasma polyanthum Ridley | |
| Polynome | Polynome Salisbury, Gen. Pl. 12. 1866. | TYPE: Dioscorea alata Linnaeus Lectotypified by Caddick et al., Taxon 51: 108. 2002. | |
| Rajania | Rajania Linnaeus, Sp. Pl. 1032. 1753. | TYPE: Rajania hastata Linnaeus Lectotypified by Britton & Millspaugh, Bahama Fl. 80. 1920. | |
| Rhizemys | Rhizemys Rafinesque, Fl. Tellur. 4: 26. 1838 ("1836"). | TYPE: = Testudinaria Salisbury ex Burchell 1824. | |
| Sismondaea | Sismondaea Delponte, Mem. Reale Accad. Sci. Torino, ser. 2. 14: 394. 1854. | TYPE: Sismondaea dioscoreoides Delponte | |
| Strophis | Strophis Salisbury, Gen. Pl. 12. 1866. | TYPE: Dioscorea cirrhosa Loureiro | |
| Tamus | Tamus Linnaeus, Sp. Pl. 1028. 1753. | TYPE: Tamus communis Linnaeus Lectotypified by M. L. Green, Prop. Brit. Bot. 191. 1929. | |
| Testudinaria | Testudinaria Salisbury ex Burchell, Trav. S. Africa 2: 147. 1824. | TYPE: Testudinaria elephatipes (L'Heritier de Brutelle) A. Dickson (Dioscorea elephantipes L'Heritier de Brutelle) Lectotypified by E. Phillips, Gen. S. African Pl., ed. 2. 208. 1951. | |
| Ubium | Ubium Cothenius, Disp. 25. 1790. | TYPE: Ubium quadrifarium J. F. Gmelin |