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 micranthum

HABIT Perennial; caespitose. Culms erect, or geniculately ascending; 15–20 cm long. Culm-internodes smooth; distally glabrous. Culm-nodes bearded. Lateral branches ample. Ligule a ciliolate membrane. Leaf-blades flat, or conduplicate; 5–10 cm long; 1.5–2.5 mm wide; pruinose. Leaf-blade apex acute.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; 1–2 cm long. Rhachis fragile at the nodes; subterete; ciliate on margins. Rhachis hairs 0.5–0.8 mm long. Rhachis internodes filiform. Rhachis internode tip oblique; 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; with 0.2–0.5 mm long hairs.

STERILE SPIKELETS Companion sterile spikelets well-developed; containing empty lemmas; obovate; 2.5–3 mm long; longer than fertile; persistent. Companion sterile spikelet glumes coriaceous; keeled; 5–9 -veined; pitted; pilose (on keel). 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; 2–2.5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pilose; base obtuse; attached obliquely. Spikelet callus hairs 0.5–0.8 mm long; 0.25 length of spikelet.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume elliptic; 1 length of spikelet; cartilaginous; without keels; 4 -veined. Lower glume primary vein ciliate. Lower glume surface concave; pitted; glabrous. Lower glume apex acute. Upper glume lanceolate; 1 length of spikelet; without keels. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret hyaline. Fertile lemma linear; hyaline; without keel. Lemma apex entire; awned; 1 -awned. Principal lemma awn apical; geniculate; 16–22 mm long overall; with twisted column. Column of lemma awn puberulous. Palea absent or minute.

FLOWER Anthers 3; 1.25–2 mm long.

DISTRIBUTION Asia-temperate: Arabia.

NOTES Andropogoneae. TAC 1997.

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