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.

Hordeum flexuosum

HABIT Annual, or perennial. Culms erect; 15–50 cm long; 2–5 -noded. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane; 1 mm long; truncate. Leaf-blades flat, or convolute; 5–10 cm long; 1–3 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; bilateral; 4–7 cm long; 3–5 mm wide. Rhachis fragile at the nodes; flattened; glabrous on margins, or ciliate on margins. Spikelet packing broadside to rhachis. Rhachis internodes oblong; 1–1.5 mm long; falling with spikelet above.

Spikelets in threes. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 2 in the cluster. Pedicels oblong; 0.5 mm long.

STERILE SPIKELETS Companion sterile spikelets well-developed; containing empty lemmas; lanceolate; dorsally compressed; 6–8 mm long; shorter than fertile; deciduous with the fertile. Companion sterile spikelet glumes markedly unequal in width (subulate & lanceolate); coriaceous and subulate; 6–8 mm long; dentate; 2 -fid; awned. Companion sterile spikelet lemmas 1; 1-awned.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension, or with a barren rhachilla extension. Spikelets lanceolate; dorsally compressed; 6–8 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes collateral; similar; reaching apex of florets; gaping. Lower glume lanceolate; 6–8 mm long; 1 length of upper glume; coriaceous. Lower glume surface scabrous. Lower glume apex setaceously attenuate. Upper glume lanceolate; 6–8 mm long; coriaceous. Upper glume apex setaceously attenuate.

FLORETS Fertile lemma lanceolate; 6–8 mm long; coriaceous; without keel; 5 -veined. Lemma surface glabrous, or puberulous. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn 2–4 mm long overall. Palea 1 length of lemma. Rhachilla extension 0–0.2 mm long.

FLOWER Lodicules 2. Anthers 3; 3 mm long. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp; ovoid; sulcate on hilar side; 3 mm long; hairy at apex. Hilum linear.

DISTRIBUTION South America: southern South America.

NOTES Triticeae. Fl Pat 1995.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.