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.

Chrysopogon argutus

HABIT Perennial; caespitose. Rhizomes short. Basal innovations intravaginal; flabellate. Culms erect; 30–100 cm long. Ligule a fringe of hairs. Leaf-blades flat, or conduplicate; 10–30 cm long; 3–10 mm wide; stiff. Leaf-blade margins scabrous. Leaf-blade apex abruptly acute.

INFLORESCENCE Inflorescence a panicle with branches tipped by a raceme.

Panicle contracted; oblong; 8–25 cm long. Primary panicle branches whorled at most nodes; simple.

Racemes 3–8 cm long; bearing few fertile spikelets; bearing 3–6 fertile spikelets on each. Rhachis fragile at the nodes. Rhachis internodes filiform. Rhachis internode tip oblique. Raceme-bases filiform; pubescent; hairy at tip.

Spikelets appressed; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels filiform; 6–8 mm long.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; linear; dorsally compressed; shorter than fertile; separately deciduous. Companion sterile spikelet glumes coriaceous; 2–5 mm long; muticous. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; compressed slightly; 6.5–8 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate; 1.5–2 mm long; bearded; base obtuse; attached obliquely. Spikelet callus hairs white, or yellow.

GLUMES Glumes dissimilar; reaching apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; coriaceous; without keels. Lower glume surface spinose; rough generally, or on flanks. Upper glume lanceolate; chartaceous; 1-keeled. Upper glume primary vein scabrous. Upper glume muticous, or mucronate, or awned; 2 -awned. Upper glume awn 0–3 mm long.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; hyaline; 2 -veined. Fertile lemma oblong; 2 mm long; hyaline; without keel; 1 -veined. Lemma apex entire; awned; 1 -awned. Principal lemma awn flexuous; 10–25 mm long overall. Palea hyaline; 0 -veined; without keels.

FLOWER Anthers 3.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Africa: western Indian ocean.

NOTES Andropogoneae. CEH.

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