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 oliganthus

HABIT Perennial; caespitose. Rhizomes short. Basal innovations intravaginal; flabellate. Culms erect; 60–120 cm long; 4–6 -noded. Ligule a fringe of hairs. Leaf-blades 25–55 cm long; 2.5–5 mm wide; stiff. Leaf-blade margins scabrous. Leaf-blade apex obtuse, or abruptly acute.

INFLORESCENCE Inflorescence a panicle with branches tipped by a raceme.

Panicle open, or contracted; lanceolate; 11–17 cm long; 1.2–5.5 cm wide. Primary panicle branches whorled at most nodes; simple. Panicle branches flexuous.

Racemes 1.2–2.2 cm long; bearing few fertile spikelets; bearing 2–3 fertile spikelets on each. Rhachis fragile at the nodes. Rhachis internodes filiform; 3.5–6.5 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; 1.5–3.5 mm long.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; linear; dorsally compressed; 4.5–7.5 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; 7 -veined; scabrous; 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; 4.5–7 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate; 1–2 mm long; bearded; base obtuse; attached obliquely. Spikelet callus hairs white; 0.2–0.3 length of spikelet (0.8–1.5mm).

GLUMES Glumes dissimilar; reaching apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; cartilaginous; without keels; 4–5 -veined. Lower glume surface spinose; rough on flanks. Upper glume lanceolate; cartilaginous; 1-keeled. Upper glume primary vein spinulose. Upper glume muticous, or mucronate.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 0.5–0.7 length of spikelet; hyaline; 2 -veined; ciliolate on margins. Fertile lemma oblong; 3–4 mm long; hyaline; without keel; 1 -veined. Lemma margins ciliolate. Lemma apex entire; awned; 1 -awned. Principal lemma awn apical; straight; 1.5–15 mm long overall. Palea 0.3–0.5 length of lemma; hyaline; 0 -veined; without keels.

FLOWER Anthers 3; 1.1–1.2 mm long.

FRUIT Caryopsis with adherent pericarp; oblong; 3 mm long.

DISTRIBUTION Australasia: Australia.

NOTES Andropogoneae. Blake.

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