Coix L.

First published in Sp. Pl.: 972 (1753)
This genus is accepted
The native range of this genus is Indian Subcontinent to Taiwan and W. Malesia, N. Queensland.

Descriptions

nonem

Morphology General Habit
Annual (3), or perennial (1). Rhizomes absent (3), or elongated (1). Culms rambling (1/1); 60-146.2-250 cm long; spongy (1), or firm (3). Ligule an eciliate membrane. Leaf-blades linear, or lanceolate (3).
Morphology Reproductive morphology Inflorescences
Monoecious; with a male and a female inflorescence subtended by the same spatheole. Synflorescence compound; paniculate. Inflorescence composed of racemes; axillary; deciduous as a whole; subtended by a spatheole; exserted, or enclosed. Spatheole ovate (3), or globose (2); indurate. Peduncle widened at apex; disarticulating. Racemes single; bearing a triad of spikelets. Rhachis obsolete. Spikelets in threes. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 2 in the cluster. Male spikelets sessile (2/3), or sessile and pedicelled (1/3), or pedicelled (1/3); 2 in a cluster (3), or 3 in a cluster (2). Pedicels linear. Male inflorescence unlike female; a single raceme. Male spikelets distinct from female; elliptic (1/2), or ovate (1/2). Male spikelet glumes 2; muticous. Male spikelet lemma muticous.
Morphology Reproductive morphology Inflorescences Spikelets
Companion sterile spikelets represented by barren pedicels. Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; 4-7.25-9 mm long; falling entire; deciduous with accessory branch structures.
Sterile
Companion sterile spikelets represented by barren pedicels.
Fertile
Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; 4-7.25-9 mm long; falling entire; deciduous with accessory branch structures.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes reaching apex of florets. Lower glume lanceolate (1), or oblong (1), or ovate (1), or orbicular (2); membranous (3), or chartaceous (1); without keels. Lower glume surface convex (3), or flat (1). Lower glume apex acute (1), or cuspidate (3). Upper glume oblong (1), or ovate (3); hyaline (1), or membranous (3); with undifferentiated margins (1), or hyaline margins (3); 1-keeled; 11 -veined (1/1). Upper glume apex acute (1), or cuspidate (3).
Morphology Reproductive morphology Flowers Florets
Basal sterile florets barren; with palea (1), or without significant palea (3). Lemma of lower sterile floret lanceolate (1), or oblong (1), or ovate (3); membranous; 5 -veined (1/2), or 7 -veined (1/2); acute (1), or acuminate (1), or cuspidate (2). Fertile florets female. Fertile lemma lanceolate (2), or oblong (1), or ovate (2); membranous; of similar consistency above (1), or firmer above (3); keeled; 3-4 -veined (1/2), or 5 -veined (2/2). Lemma lateral veins obscure (1/1). Lemma surface without grooves (2), or with 2 longitudinal grooves (2). Lemma apex acute (1), or acuminate (1), or rostrate (2). Palea hyaline; 2 -veined; without keels.
Morphology Reproductive morphology Flowers
Lodicules absent (3/3), or 2 (3/3); fleshy (3/3). Anthers 3. Stigmas 2; papillose.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp; orbicular (2/2). Embryo 1 length of caryopsis.
sex Male
Male inflorescence unlike female; a single raceme. Male spikelets distinct from female; elliptic (1/2), or ovate (1/2). Male spikelet glumes 2; muticous. Male spikelet lemma muticous.
Distribution
Europe (1), or Africa (1), or Temperate Asia (3), or Tropical Asia (3), or Australasia (3), or Pacific (1), or North America (1), or South America (1).
[GB]

Gramineae, W. D. Clayton, S. M. Phillips And S. A. Renvoize. Flora of Tropical East Africa. 1974

Morphology General Habit
Robust annuals or perennials with erect or floating culms and broad flat leaf-blades; ligule short, membranous
Morphology Reproductive morphology Inflorescences
Inflorescences terminal and axillary, often numerous, each subtended by a globose or elongated ivory-like cupule (a modified leaf-sheath within which is a membranous prophyll) and comprising 2 racemes; female raceme enclosed by the cupule, and consisting of 1 sessile spikelet accompanied by 2 barren pedicels; male raceme exserted from the mouth of the cupule, the spikelets imbricate and borne in pairs or threes, one pedicelled, the other(s) sessile
Morphology Reproductive morphology Inflorescences Spikelets
Female spikelet; glumes orbicular, membranous with a cartilaginous beak, the upper keeled; lower floret represented by an orbicular membranous lemma; upper floret with membranous lemma and palea, the 2 stigmas exserted from the cupule Male spikelet lanceolate to elliptic-oblong; lower glume flat on the back, 2-keeled, the keels winged above; upper glume boat-shaped; florets 2, with membranous lemma and palea, the lower as long as the spikelet, the upper shorter and sometimes barren
sex Female
Female spikelet; glumes orbicular, membranous with a cartilaginous beak, the upper keeled; lower floret represented by an orbicular membranous lemma; upper floret with membranous lemma and palea, the 2 stigmas exserted from the cupule
sex Male
Male spikelet lanceolate to elliptic-oblong; lower glume flat on the back, 2-keeled, the keels winged above; upper glume boat-shaped; florets 2, with membranous lemma and palea, the lower as long as the spikelet, the upper shorter and sometimes barren
Morphology Reproductive morphology Fruits
Caryopsis subglobose to ellipsoid.
[FTEA]

Sources

  • Flora of Tropical East Africa

    • Flora of Tropical East Africa
    • http://creativecommons.org/licenses/by-nc-sa/3.0
  • GrassBase - The Online World Grass Flora

    • Clayton, W.D., Vorontsova, M.S., Harman, K.T. and Williamson, H. (2006 onwards). GrassBase - The Online World Grass Flora.
    • http://creativecommons.org/licenses/by-nc-sa/3.0
  • Herbarium Catalogue Specimens

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0
  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0