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 queenslandicum

HABIT Perennial; caespitose. Culms erect; 40–80 cm long; 4–5 -noded. Culm-nodes bearded. Leaf-sheaths hirsute; with tubercle-based hairs. Ligule a ciliolate membrane; 1–1.5 mm long. Leaf-blades 9–18 cm long; 3–5 mm wide. Leaf-blade surface hirsute; with tubercle-based hairs. Leaf-blade margins scaberulous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; 5–10 cm long; bearing 15–30 fertile spikelets on each. Rhachis fragile at the nodes; subterete; ciliate on margins. Rhachis hairs on upper part of internode and on lower part of internode; 2–3 mm long. Rhachis internodes linear; 2.5 mm long.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; without a translucent median line; ciliate; hairy above; with 2–3 mm long hairs.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; lanceolate; 6 mm long; shorter than fertile; separately deciduous. Companion sterile spikelet glumes 11 -veined. Companion sterile spikelet lemmas enclosed by glumes; muticous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 7.5–8.5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pubescent; base obtuse; attached transversely. Spikelet callus hairs 0.3 mm long.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume oblong; 1 length of spikelet; coriaceous; without keels; keel-less except near apex; winged on margins; winged above; 11 -veined. Lower glume surface convex. Lower glume apex dentate. Upper glume lanceolate; coriaceous; 1-keeled; 3 -veined. Upper glume primary vein grooved on either side. Upper glume apex acuminate.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret 5 mm long; hyaline. Fertile lemma linear; 3 mm long; hyaline; without keel; 1 -veined. Lemma apex entire; awned; 1 -awned. Principal lemma awn apical; geniculate; 20 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FLOWER Anthers 2; 1 mm long.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Australasia: Australia.

NOTES Andropogoneae. Simon 1993.

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