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 armatum

HABIT Annual; caespitose. Culms geniculately ascending; 30–45 cm long. Culm-nodes bearded. Ligule an eciliate membrane; 1–1.5 mm long. Leaf-blades 10–15 cm long; 4–6 mm wide. Leaf-blade surface pilose; hairy on both sides; with tubercle-based hairs.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 3–5; digitate; 1.3–3.8 cm long. Rhachis fragile at the nodes; subterete; ciliate on margins. Rhachis internodes linear. Raceme-bases filiform; dichotomously branched; 4–8 mm long; pilose; hairy in axils.

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

STERILE SPIKELETS Basal sterile spikelets well-developed; 2 in number (lower raceme); 2 in upper raceme; male; elliptic; 3 mm long; equalling fertile. Basal sterile spikelet glumes chartaceous; tuberculate; setose; lemmas awnless.

Companion sterile spikelets well-developed; male; elliptic; 3 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; tuberculate; setose (hairs 5–7mm long); ciliate on margins. Companion sterile spikelet lemmas enclosed by glumes; muticous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; obtuse; 3 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pubescent; base obtuse; attached transversely.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume elliptic; 1 length of spikelet; cartilaginous; without keels. Lower glume surface convex; pitted (1 pit); pubescent; hairy below. Lower glume margins ciliate. Lower glume apex obtuse. Upper glume elliptic; cartilaginous; 1-keeled. Upper glume surface pubescent; hairy above. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret linear, or oblong; hyaline; obtuse. Fertile lemma linear; hyaline; without keel; 1 -veined. Lemma apex entire; awned; 1 -awned. Principal lemma awn apical; geniculate; 20–25 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FLOWER Anthers 3.

DISTRIBUTION Asia-tropical: India.

NOTES Andropogoneae. WDC.

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