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.

Oplismenus hirtellus

HABIT Perennial. Culms prostrate; 15–100 cm long; rooting from lower nodes. Ligule a ciliate membrane. Leaf-blades lanceolate to ovate; 1–13 cm long; 4–20 mm wide. Leaf-blade venation with obscure cross veins.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 3–9; borne along a central axis; unilateral; 0.5–3 cm long. Central inflorescence axis 3–15 cm long. Rhachis angular; glabrous on surface, or pilose on surface. Spikelet packing contiguous; regular; 2 -rowed.

Spikelets in pairs. Fertile spikelets sessile and pedicelled; 2 in the cluster; subequal, or the lower smaller. Pedicels oblong.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 2–4 mm long; falling entire.

GLUMES Glumes similar, or dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 1 length of upper glume; 0.5–0.7 length of spikelet; herbaceous; 1-keeled; 5 -veined. Lower glume surface glabrous, or pubescent. Lower glume apex acute; awned; 1 -awned. Lower glume awn 3–14 mm long; viscid. Upper glume ovate; herbaceous; 1-keeled; 5–7 -veined. Upper glume surface glabrous, or pubescent. Upper glume apex obtuse; muticous, or awned. Upper glume awn 2–4 mm long.

FLORETS Basal sterile florets barren; with palea, or without significant palea. Lemma of lower sterile floret ovate; 1 length of spikelet; membranous; 1-keeled; 7–11 -veined; glabrous, or pubescent; emarginate; mucronate. Fertile lemma oblong; dorsally compressed; 2–2.5 mm long; coriaceous; shiny; without keel; 7 -veined. Lemma margins involute. Lemma apex acute; laterally pinched. Palea involute; coriaceous; without keels.

DISTRIBUTION Africa: Macaronesia, west tropical, west-central tropical, northeast tropical, east tropical, southern tropical, south, and western Indian ocean. Asia-temperate: Arabia. Asia-tropical: India, Malesia, and Papuasia. Australasia: Australia and New Zealand. Pacific: southwestern, south-central, northwestern, and north-central. North America: north-central USA, south-central USA, southeast USA, and Mexico. South America: Mesoamericana, Caribbean, northern South America, western South America, Brazil, and southern South America.

NOTES Paniceae. FTEA.

ADDITIONAL CHARACTERS Spikelet pairs 0.5–4mm apart.

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