GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Coix

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).

INFLORESCENCE 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.

STERILE SPIKELETS Companion sterile spikelets represented by barren pedicels.

FERTILE SPIKELETS 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.

GLUMES 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); without pits. 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).

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; wingless; 3–4 -veined (1/2), or 5 -veined (2/2). Lemma lateral veins obscure (1/1). Lemma surface unwrinkled; 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.

FLOWER Lodicules absent (3/3), or 2 (3/3); fleshy (3/3). Anthers 3. Stigmas 2; papillose.

FRUIT Caryopsis with adherent pericarp; orbicular (2/2). Embryo 1 length of caryopsis.

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).

Please cite this publication as detailed in How to Cite Version: 27th January 2014.