GrassBase - The Online World Grass Flora


W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Thelepogon australiensis

HABIT Annual. Culms erect; 70–140 cm long. Culm-nodes glabrous. Lateral branches sparse. Leaf-sheaths pilose; with tubercle-based hairs. Ligule a ciliolate membrane; 1 mm long. Leaf-blade base broadly rounded. Leaf-blades lanceolate; 5–12 cm long; 6–10 mm wide. Leaf-blade surface pilose; with tubercle-based hairs. Leaf-blade margins tuberculate-ciliate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1–3; single, or paired, or digitate; 2.5–5.5 cm long; bearing 10–13 fertile spikelets on each. Rhachis fragile at the nodes; angular; pilose on surface. Rhachis internodes linear; 3.5 mm long. Rhachis internode tip transverse; cupuliform. Raceme-bases filiform; 8–13 mm long; pubescent.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; foliaceous; 3 mm long; ciliate.

STERILE SPIKELETS Companion sterile spikelets represented by barren pedicels.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets. Spikelets lanceolate, or elliptic; dorsally compressed; 6–7 mm long; 1.5 mm wide; falling entire; deciduous with accessory branch structures. Spikelet callus pubescent; base obtuse; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume ovate; 1 length of spikelet; indurate; without keels; 7 -veined. Lower glume surface muricate; rough on flanks. Lower glume apex acute. Upper glume elliptic; chartaceous; 1-keeled; keeled above; 3 -veined. Upper glume primary vein scabrous. Upper glume apex acuminate.

FLORETS Basal sterile florets male; without significant palea. Lemma of lower sterile floret elliptic; 4 mm long; hyaline. Fertile lemma lanceolate; 4 mm long; hyaline; without keel. Lemma apex lobed; 2 -fid; awned. Principal lemma awn from a sinus; geniculate; 12–16 mm long overall; with twisted column. Column of lemma awn glabrous. Palea 2 mm long; hyaline; without keels.

FLOWER Anthers 1.2 mm long.

DISTRIBUTION Australasia: Australia.

NOTES Andropogoneae. Simon 1993.

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