Dioscoreaceae R.Br.
  • Prodr. 294. 1810. (27 Mar 1810)
  • Yam Family


Cite taxon page as 'WFO (2020): Dioscoreaceae R.Br. Published on the Internet;http://www.worldfloraonline.org/taxon/wfo-7000000192. Accessed on: 19 Sep 2020'

General Information

Herbs twining or woody vines, rarely erect, small herbs. Rootstock rhizomatous or tuberous. Stem twining to left or right, pubescent or glabrous, sometimes prickly. Leaves alternate or opposite, petiolate, simple or palmately compound, basal veins 3--13, interstitial veins reticulate; leaflets of palmately compound leaves often ovate or lanceolate. Flowers usually unisexual (when plants dioecious, rarely monoecious), sometimes bisexual, solitary, clustered, or in cymules, these in a spike, raceme, or thyrse, these sometimes grouped into panicles. Male flowers: perianth lobes 6, in 2 whorls, basally connate or free; stamens 6, sometimes 3 reduced to staminodes or absent, inserted on perianth or receptacle; ovary rudimentary or absent. Female flowers: similar to male ones; staminodes 3, 6, or absent; ovary inferior, 3-loculed, ovules usually 2 per locule (more than 2 in a few small genera), placentation axile; styles 3, free. Fruit a capsule, berry, or samara. Seeds with a membranous wing or not; endosperm present; embryo small.

  • Provided by: [B].Flora Of CHina @ efloras.org
    • Source: [
    • 3
    • ]. 

    Vines [herbs], geophytes perennating from fleshy rhizomes or tubers. Stems renewed annually or occasionally persisting for more than a single growing season, twining-climbing, procumbent, or seldom erect; vascular bundles commonly arranged in 2 concentric circles. Leaves alternate, opposite, or whorled at basal nodes; blades simple or occasionally digitately compound, typically cordate, reticulate-veined; principal veins arcuate, ascending from base to apex; margins entire or sometimes palmately lobed; stipules absent, rarely stipulate, never with tendrils; petioles typically with distinct pulvinus at each end. Inflorescences axillary, solitary or in fascicles of 2–7, branched and paniculate, or unbranched and spicate or racemose, ultimate inflorescence unit cymose, sessile or pedunculate, often reduced to 1 flower. Flowers unisexual, staminate and pistillate flowers on different plants, rarely staminate and pistillate flowers on same plant or bisexual; perianth epigynous, rotate, campanulate, or funnelform; tepals 6, petaloid, in 2 similar whorls of 3, connate at least basally; stamens 6, in 2 whorls of 3, inner whorl sometimes sterile or absent; filaments distinct [connate basally or completely into tube], inserted at base of perianth; anthers 2-locular, tetrasporangiate, dehiscing by longitudinal slits, thecae distinct or sometimes connate, rarely divided by a long-appendiculate connective; pistils 3; ovary (1–)3-locular, ovules anatropous, 2(–many) per locule, placentation axile or parietal; styles 3, ± distinct. Fruits capsular, rarely baccate or samarate, dehiscence loculicidal. Seeds flattened or globose, winged or unwinged, embryo small, endosperm copious, starchless.

  • Provided by: [C].Flora of North America @ efloras.org
    • Source: [
    • 4
    • ]. 

    Morphology

    Style 3, free or connate

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Staminodes 0, 3 or 6

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Ovary inferior, 3-locular

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Rudimentary ovary frequent

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Female inflorescences: spikes looser, longer than the male ones, solitary or paired or sometimes more numerous, in the leaf axils

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Stamens 6, or 3 with or without 3 staminodes

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Filaments free or shortly connate; anthers 2-locular

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Bracteole generally present in oblique position

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Flowers placed singly along the axis or in short few-flowered lateral cymules

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Male flowers sessile or shortly pedicelled

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Flowers small, inconspicuous, actinomorphic

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Inflorescence spicate, racemose or paniculate

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Plants dioecious; exceptionally on the same inflorescence are clustered male and female flowers6

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Leaves moving, following the conditions of lighting

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Basal leaves often reduced

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Petiole generally twisted and sometimes jointed at the base or with more or less leathery auricles

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Leaves alternate or opposite (sometimes both on the same plant), often cordate, entire or lobulate, more or less digitately nerved or palmately compound, acumen often large and glandulose

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Stems glabrous or pilose

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Male inflorescences: spikes generally several in the leaf axils, sometimes clustered in racemes or compound panicles

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Perianth campanulate or spreading, 6-lobed, lobes 2-seriate, often connate at the base

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Seeds winged, with albumen

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Fruits (in the tropical African species) 3-valved capsules

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Placentation axile: 2 anatropous ovules in each loculus

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Climbers (at least the West African species), spiny or not, annual or perennial with tubers annually renewed or perennial

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Tubers toxic or edible, often protected by thorny roots

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Aerial tubers (bulbils) present or absent

  • Provided by: [E].Plants Of the World Online Portal - FWTA
    • Source: [
    • 1
    • ]. 

    Perianth segments biseriate, usually united basally

  • Provided by: [D].Plants Of the World Online Portal - FTEA
    • Source: [
    • 2
    • ]. 

    Stamens (3, 4) 6

  • Provided by: [D].Plants Of the World Online Portal - FTEA
    • Source: [
    • 2
    • ]. 

    Leaves alternate or opposite, often ovate-cordate, but sometimes with 3–7 digitate leaflets

  • Provided by: [D].Plants Of the World Online Portal - FTEA
    • Source: [
    • 2
    • ]. 

    Flowers bisexual or unisexual, the latter usually dioecious

  • Provided by: [D].Plants Of the World Online Portal - FTEA
    • Source: [
    • 2
    • ]. 

    Twining herbs with annual stems arising from tubers or rhizomes, rarely stems self-supporting

  • Provided by: [D].Plants Of the World Online Portal - FTEA
    • Source: [
    • 2
    • ]. 

    Ovary inferior, rarely semi-inferior or superior, (1)3-locular

  • Provided by: [D].Plants Of the World Online Portal - FTEA
    • Source: [
    • 2
    • ]. 

    Fruit a dehiscent capsule, samara or berry

  • Provided by: [D].Plants Of the World Online Portal - FTEA
    • Source: [
    • 2
    • ]. 

    Literature

    SELECTED REFERENCES

    Al-Shehbaz, I. A. and B. G. Schubert. 1989. The Dioscoreaceae in the southeastern United States. J. Arnold Arbor. 70: 57–95. Ayensu, E. S. 1972. Dioscoreales. In: C. R. Metcalfe, ed. 1960+. Anatomy of the Monocotyledons. 8+ vols. Oxford. Vol. 6. Bouman, F. 1995. Seed structure and systematics in Dioscoreales. In: P. J. Rudall et al., eds. 1995. Monocotyledons: Systematics and Evolution. 2 vols. Kew. Vol. 1, pp. 139–156. Burkill, I. H. 1960. The organography and evolution of the Dioscoreaceae, the family of yams. J. Linn. Soc., Bot. 56: 319–407. Caddick, L. R. et al. 1998. Microsporogenesis and pollen morphology in Dioscoreales and allied taxa. Grana 37: 321–336. Caddick, L. R. et al. 2000. Yams and their allies: Systematics of Dioscoreales. In: K. L. Wilson and D. A. Morrison, eds. 2000. Monocots: Systematics and Evolution. Melbourne. Pp. 475–487. Coursey, D. G. 1967. Yams: An Account of the Nature, Origins, Cultivation and Utilisation of the Useful Members of the Dioscoreaceae. London. Huber, H. 1998. Dioscoreaceae. In: K. Kubitzky et al., eds. 1990+. The Families and Genera of Vascular Plants. 4+ vols. Berlin etc. Vol. 3, pp. 216–235. Knuth, R. 1924. Dioscoreaceae. In: H. G. A. Engler, ed. 1900–1953. Das Pflanzenreich…. 107 vols. Berlin. Vol. 87 [IV,43], pp. 1–387. Queva, C. 1894. Recherches sur l’Anatomie de l’Appareil Vegetatif des Taccacées & Dioscorées. Lille.

  • Provided by: [C].Flora of North America @ efloras.org
    • Source: [
    • 4
    • ]. 

    Other Local Names

    NameLanguageCountry
    Yam Family

     Information From

    Dioscoreaceae
    World Flora Online Data. 2017.
    • A CC0 1.0 Universal (CC0 1.0).
    Flora Of CHina @ efloras.org
    http://www.efloras.org/flora_page.aspx?flora_id=2
    'Flora of China @ eFloras (2008). Published on the Internet http://www.efloras.org/flora_page.aspx?flora_id=2 [accessed August 2016]' Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
    • B Missouri Botanical Garden
    Flora of North America @ efloras.org
    http://www.efloras.org/flora_page.aspx?flora_id=1
    'Flora of North America @ eFloras (2008). Published on the Internet http://www.efloras.org/flora_page.aspx?flora_id=1 [accessed August 2016]' Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
    • C Flora of North America Association
    Plants Of the World Online Portal - FTEA
    https://www.kew.org/science/who-we-are-and-what-we-do/strategic-outputs-2020/plants-of-the-world-online
    http://www.plantsoftheworldonline.org/terms-and-conditions
    • D
    Plants Of the World Online Portal - FWTA
    https://www.kew.org/science/who-we-are-and-what-we-do/strategic-outputs-2020/plants-of-the-world-online
    http://www.plantsoftheworldonline.org/terms-and-conditions
    • E The Trustees of the Royal Botanic Gardens, Kew
    World Flora Online consortium
    http://www.worldfloraonline.org/organisation/WFO
    World Flora Online Data. 2018.
    • F CC0 1.0 Universal (CC0 1.0).