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.

Cymbopogon queenslandicus

HABIT Perennial; caespitose. Butt sheaths glabrous, or sparsely hairy. Culms erect; 100 cm long. Culm-internodes distally glabrous, or pubescent. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane; 2–5 mm long. Leaf-blades 20–40 cm long; 3–10 mm wide; aromatic. Leaf-blade surface scaberulous; rough on both sides; glabrous.

INFLORESCENCE Synflorescence compound; scanty; 40 cm long. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; enclosed. Spatheole elliptic; 2–2.2 cm long. Peduncle glabrous.

Racemes 2; paired; deflexed; 1.6–2 cm long. Rhachis fragile at the nodes; semiterete; pilose on surface; ciliate on margins. Rhachis internodes linear. Rhachis internode tip transverse; cupuliform. Raceme-bases flattened; unequal (the longer measured).

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; semiterete; ciliate.

STERILE SPIKELETS Basal sterile spikelets absent.

Companion sterile spikelets well-developed; containing empty lemmas; lanceolate; 5–6 mm long; as long as fertile, or longer than fertile; deciduous with the fertile. Companion sterile spikelet glumes chartaceous; 7(–9) -veined; acuminate; 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, or oblong; dorsally compressed; 5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus base obtuse; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume linear, or oblong; 1 length of spikelet; chartaceous; 2-keeled; keeled all along; keeled laterally; winged on keel; winged narrowly. Lower glume intercarinal veins distinct; 2–4 in number. Lower glume surface concave; impressed below. Upper glume lanceolate; 1-keeled. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret hyaline. Fertile lemma lanceolate; hyaline; without keel. Lemma apex lobed; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 10–12 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FLOWER Anthers 3.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Australasia: Australia.

NOTES Andropogoneae. Soenarko 1993.

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