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 tuberculatum

HABIT Perennial. Culms erect; 100–150 cm long; wiry. Culm-nodes glabrous. Lateral branches ample. Leaf-sheaths glabrous on surface. Leaf-sheath auricles erect. Ligule a ciliolate membrane; 4–6 mm long; acute. Leaf-blades 20–40 cm long; 4–6 mm wide; stiff; glaucous. Leaf-blade midrib widened. Leaf-blade surface ribbed; scabrous; rough on both sides; glabrous. Leaf-blade margins scabrous.

INFLORESCENCE Synflorescence compound; linear; 20–35 cm long. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; embraced at base by subtending leaf. Spatheole linear.

Racemes 1; single; 2.5–3 cm long. Rhachis fragile at the nodes; subterete; ciliate on margins. Rhachis internodes filiform. Rhachis internode tip flat.

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

STERILE SPIKELETS Companion sterile spikelets well-developed; male; lanceolate; 5 mm long; as long as fertile. Companion sterile spikelet glumes tuberculate. Companion sterile spikelet lemmas enclosed by glumes; muticous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pubescent; base obtuse; attached obliquely.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume elliptic; 1 length of spikelet; chartaceous; without keels; 5–7 -veined. Lower glume surface flat; tuberculate; rough on veins. Lower glume apex obtuse. Upper glume lanceolate; without keels; 1 -veined. Upper glume lateral veins absent. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret 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; 16–18 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FLOWER Anthers 2; 2 mm long.

DISTRIBUTION Asia-tropical: India.

NOTES Andropogoneae. Hackel 1997.

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