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.

Dichanthium erectum

HABIT Perennial. Rhizomes short. Culms erect; slender; 30–60 cm long; wiry. Culm-internodes smooth; distally glabrous. Lateral branches lacking. Leaf-sheaths tight; with 0.9 of their length closed; mostly shorter than adjacent culm internode; without keel; glabrous on surface. Ligule an eciliate membrane. Leaf-blades erect; 3–4 cm long; 2–7 mm wide; stiff; glaucous. Leaf-blade surface glabrous; hairless throughout, or except near base.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; 3–5 cm long; bearing 5–10 fertile spikelets on each. Rhachis fragile at the nodes; subterete; ciliate on margins. Rhachis internodes filiform; 2.5–3 mm long.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels filiform; 1.5 mm long; without a translucent median line; ciliate.

STERILE SPIKELETS Basal sterile spikelets well-developed; 2–4 in number; barren, or male; smaller than fertile. Basal sterile spikelet lemmas awnless.

Companion sterile spikelets well-developed; containing empty lemmas, or male; oblong; as long as fertile; separately deciduous. Companion sterile spikelet glumes without depressions, or pitted (1–3 pits). Companion sterile spikelet lemmas enclosed by glumes; muticous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate, or elliptic; dorsally compressed; 4.5–5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pilose; base obtuse; attached transversely.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate, or elliptic; 1 length of spikelet; chartaceous; without keels; winged on margins; winged narrowly; 6–7 -veined. Lower glume primary vein ciliolate (above). Lower glume lateral veins obscure. Lower glume surface convex. Lower glume apex acute. Upper glume oblong; 1-keeled. Upper glume muticous, or mucronate.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret 3 mm long; hyaline; 0 -veined; without midvein; without lateral veins. Fertile lemma linear; hyaline; without keel; 1 -veined. Lemma apex entire; awned; 1 -awned. Principal lemma awn apical; geniculate; 15–20 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FLOWER Anthers 3.

DISTRIBUTION Asia-tropical: Malesia.

NOTES Andropogoneae. Jansen 2001.

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