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 elongatus

HABIT Perennial; caespitose. Rhizomes short. Basal innovations intravaginal; flabellate. Culms erect; 150–250 cm long; 7 -noded. Ligule a fringe of hairs. Leaf-blades conduplicate; 25–50 cm long; 4–8 mm wide; stiff. Leaf-blade surface pilose; sparsely hairy; hairy adaxially; with tubercle-based hairs. Leaf-blade margins scabrous. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle with branches tipped by a raceme. Peduncle smooth.

Panicle contracted; lanceolate; 15–30 cm long; 2–3 cm wide. Primary panicle branches whorled at most nodes; simple. Panicle branches straight.

Racemes 1.5–2.5 cm long; bearing few fertile spikelets; bearing 3–6 fertile spikelets on each. Rhachis fragile at the nodes. Rhachis internodes filiform; 3–4 mm long. 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; 2–3 mm long.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; linear; dorsally compressed; 5.5–6.5 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; muticous. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets linear; laterally compressed; compressed slightly; 5–7 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate; 1.6–2.2 mm long; bearded; base obtuse; attached obliquely. Spikelet callus hairs white; 0.5 length of spikelet (2–3mm).

GLUMES Glumes dissimilar; reaching apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; coriaceous; without keels; 5–8 -veined. Lower glume surface spinose; rough on flanks. Upper glume lanceolate; coriaceous; 1-keeled. Upper glume primary vein spinulose. Upper glume muticous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 1 length of spikelet; hyaline; 2 -veined; ciliolate on margins. Fertile lemma oblong; 4–6 mm long; hyaline; without keel; 3 -veined. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 4–7 mm long overall; with a straight or slightly twisted column. Palea 0.3–0.5 length of lemma; hyaline; 0 -veined; without keels.

FLOWER Anthers 3; 1 mm long.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Asia-tropical: Papuasia. Australasia: Australia.

NOTES Andropogoneae. Blake.

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