Desmostachya bipinnata

HABIT Perennial; caespitose; clumped densely. Rhizomes elongated; scaly. Butt sheaths scarious; pallid, or dark brown; glabrous. Basal innovations intravaginal; flabellate. Culms erect; 50–100 cm long. Leaves mostly basal. Leaf-sheaths as wide as blade at the collar; smooth; glabrous on surface. Ligule a ciliate membrane; 0.5–1 mm long. Leaf-blades convolute; 10–50 cm long; 2–6 mm wide; coriaceous; stiff; glaucous. Leaf-blade surface ribbed. Leaf-blade margins scabrous. Leaf-blade apex attenuate; filiform.

INFLORESCENCE Inflorescence composed of racemes.

Racemes numerous; borne along a central axis; closely spaced; in a multilateral false spike; spreading; oblong; unilateral; 1–2 cm long. Central inflorescence axis 15–40 cm long. Rhachis semiterete; puberulous on surface. Spikelet packing broadside to rhachis; crowded.

Spikelets spreading; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 2–18 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; compressed strongly; 2.5–13 mm long; falling entire. Rhachilla internodes eventually visible between lemmas.

GLUMES Glumes similar; shorter than spikelet. Lower glume ovate; 0.7–1.5 mm long; 0.5 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 1.1–2 mm long; 0.5 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume apex acute.

FLORETS Fertile florets free at tip. Fertile lemma ovate; laterally compressed; 1.5–1.8 mm long; membranous; keeled; 3 -veined. Lemma midvein scaberulous. Lemma lateral veins obscure; close to margins. Lemma apex acute. Palea oblong; 1 length of lemma; 2 -veined. Palea keels scaberulous. Palea apex entire; acute. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; fleshy; entire; emarginate. Anthers 3; linear. Stigmas 2; laterally exserted.

FRUIT Caryopsis with adherent pericarp; ovoid; trigonous; without sulcus. Embryo 0.3–0.4 length of caryopsis. Hilum punctiform. Disseminule comprising a spikelet.

DISTRIBUTION Africa: north, west tropical, and northeast tropical. Asia-temperate: western Asia, Arabia, and China. Asia-tropical: India, Indo-China, and Malesia.

NOTES Eragrostideae. WDC.

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