Dichanthium sericeum

HABIT Perennial; caespitose. Culms erect; of moderate stature; 30–80 cm long; 4 -noded. Culm-internodes channelled. Culm-nodes bearded. Lateral branches lacking, or sparse. Leaf-sheaths glabrous on surface, or pilose; with tubercle-based hairs. Ligule an eciliate membrane; 1 mm long. Leaf-blades 8–15 cm long; 2–4 mm wide; mid-green, or glaucous. Leaf-blade midrib evident. Leaf-blade surface glabrous, or pilose; with tubercle-based hairs. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1–6; single, or paired, or digitate; 4–7 cm long. Rhachis fragile at the nodes; subterete; ciliate on margins. Rhachis hairs lengthening towards internode tip; 1–1.5 mm long. Rhachis internodes linear; 2 mm long.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; 2 mm long; without a translucent median line; ciliate; hairy all along but hairs longer above; with 1–1.5 mm long hairs.

STERILE SPIKELETS Basal sterile spikelets well-developed; 2–6 in number; barren; smaller than fertile. Basal sterile spikelet lemmas awnless.

Companion sterile spikelets well-developed; containing empty lemmas; obovate; 3 mm long; shorter than fertile; separately deciduous. Companion sterile spikelet glumes 8 -veined; ciliate on margins. 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; 4 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pubescent; base obtuse; attached transversely.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume oblong; 1 length of spikelet; chartaceous; much thinner above; without keels; keel-less except near apex; 6–8 -veined. Lower glume surface flat, or concave; tuberculate (along fringe); pubescent; hairy below; with a transverse fringe of hair. Lower glume margins ciliate. Lower glume hairs 5–6 mm long. Lower glume apex truncate, or obtuse. Upper glume lanceolate; 1-keeled; 3 -veined. Upper glume apex erose; truncate.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate, or ovate; 1.5–2.5 mm long; hyaline; obtuse, or acute. Fertile lemma linear; hyaline; without keel; 1 -veined. Lemma apex entire; awned; 1 -awned. Principal lemma awn apical; geniculate; 25 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FLOWER Anthers 3; 1 mm long.

FRUIT Caryopsis with adherent pericarp; obovoid.

DISTRIBUTION Africa: southern tropical. Asia-tropical: Malesia and Papuasia. Australasia: Australia. Pacific: southwestern, south-central, and north-central. North America: south-central USA.

NOTES Andropogoneae. Fl NSW 1993.

ADDITIONAL CHARACTERS Peduncle moderately stout.

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