GrassBase - The Online World Grass Flora


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

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

Oplismenopsis najada

HABIT Perennial. Culms prostrate; 30–60 cm long; 4–12 mm diam.; spongy; rooting from lower nodes. Leaf-sheaths inflated. Ligule a ciliolate membrane; 1–1.5 mm long. Leaf-blade base broadly rounded. Leaf-blades lanceolate, or oblong; (1–)3–14 cm long; 10–27 mm wide. Leaf-blade apex acute.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 5–20; borne along a central axis; flexuous; unilateral; 2.5–12 cm long. Central inflorescence axis 10–20 cm long. Rhachis angular. Spikelet packing adaxial; lax.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels oblong; 1 mm long.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 6–8.5 mm long; falling entire.

GLUMES Glumes similar; reaching apex of florets, or shorter than spikelet; thinner than fertile lemma. Lower glume lanceolate; 0.33–0.5 length of spikelet; membranous; without keels; 3 -veined. Lower glume apex acuminate; awned; 1 -awned. Lower glume awn 3 mm long. Upper glume elliptic; 6–8.5 mm long; 1.25 length of adjacent fertile lemma; membranous; without keels; 5–7 -veined. Upper glume apex acuminate; awned; 1 -awned. Upper glume awn 3–5 mm long.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret elliptic; 6–8 mm long; 0.9–1 length of spikelet; membranous; 5 -veined; acute, or acuminate; muticous, or awned. Awn of lower sterile floret 0–1 mm long. Fertile lemma elliptic; 5–6.5 mm long; coriaceous; shiny; without keel; 5 -veined. Lemma margins involute. Lemma apex acute. Palea coriaceous.

FRUIT Hilum linear.

DISTRIBUTION South America: western South America and southern South America.

NOTES Paniceae. WDC.

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