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.

Ophiuros

HABIT Annual (2), or perennial (2). Culms erect (1/1); robust (2/2); 25–163.1–400 cm long. Lateral branches ample (1/1). Ligule an eciliate membrane. Leaf-blades linear (1), or lanceolate (2), or elliptic (1). Leaf-blade venation without cross veins (3), or with obscure cross veins (1). Leaf-blade margins cartilaginous (1/1).

INFLORESCENCE Synflorescence simple (1), or compound (3); fastigiate (1/3), or fasciculate (2/3). Inflorescence composed of racemes; terminal and axillary; subtended by an unspecialized leaf-sheath (1), or a spatheole (3); exserted (3), or embraced at base by subtending leaf (1). Spatheole linear (3/3). Peduncle widened at apex (3/3).

Racemes single; bilateral. Rhachis fragile at the nodes; subcylindrical and excavated. Spikelet packing abaxial; 2 -rowed. Rhachis internodes oblong. Rhachis internode tip transverse; crateriform.

Spikelets sunken; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels fused to internode.

STERILE SPIKELETS Companion sterile spikelets represented by barren pedicels.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 2–3.009–4 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus base truncate; with central peg; attached transversely.

GLUMES Glumes reaching apex of florets; firmer than fertile lemma. Lower glume oblong; coriaceous; without keels (2), or 2-keeled (2); wingless (3), or winged on keel (1); 7 -veined (3), or 8 -veined (2), or 9 -veined (3). Lower glume surface smooth, or cancellate (1), or areolate (2); without pits. Lower glume apex obtuse. Upper glume elliptic; membranous; 1–2 -veined (2), or 3 -veined. Upper glume apex obtuse.

FLORETS Basal sterile florets male (1), or barren (3); with palea. Lemma of lower sterile floret lanceolate (2), or oblong (1), or ovate (1); hyaline; 2 -veined (1/1). Fertile lemma linear (1), or lanceolate (2), or ovate (1); hyaline; without keel; wingless; 0 -veined (1/1). Lemma surface unwrinkled; without grooves. Palea hyaline.

FLOWER Anthers 3 (2/2).

DISTRIBUTION Africa (1), or Temperate Asia (1), or Tropical Asia (3), or Australasia (1).

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