Sorghum leiocladum

HABIT Perennial. Rhizomes absent, or short. Culms 60–150 cm long; 3–5 -noded. Culm-nodes bearded. Leaf-sheaths mostly shorter than adjacent culm internode. Leaf-sheath oral hairs lacking, or bearded. Ligule an eciliate membrane; 1–1.3 mm long; glabrous on abaxial surface. Leaf-blades curled; flat, or involute; 10–70 cm long; 1.5–3.5 mm wide. Leaf-blade midrib widened. Leaf-blade surface glabrous, or hirsute; with tubercle-based hairs. Leaf-blade apex filiform.

INFLORESCENCE Inflorescence a panicle with branches tipped by a raceme.

Panicle open; lanceolate, or oblong; 14.5–19 cm long; 2–4 cm wide. Primary panicle branches 1–6 -nate; indistinct the panicle almost racemose; 1.5–4 cm long. Panicle axis smooth, or scaberulous. Panicle branches glabrous in axils, or bearded in axils; with prominent pulvini.

Racemes 1.8–5 cm long; bearing few fertile spikelets; bearing 3–6 fertile spikelets on each. Rhachis fragile at the nodes; ciliate on margins. Rhachis internodes linear; 3–6 mm long. Rhachis internode tip transverse; cupuliform.

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

STERILE SPIKELETS Companion sterile spikelets well-developed; containing empty lemmas, or male; lanceolate; dorsally compressed; 5–8 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes membranous, or chartaceous; 5–8 -veined; pilose; muticous. Companion sterile spikelet lemmas enclosed by glumes; muticous, or 1-awned; with 0–2.5 mm long awn.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate, or oblong; dorsally compressed; 6–8 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus brief; 0.3 mm long; pilose; base obtuse. Spikelet callus hairs white, or tawny; 1–3 mm long.

GLUMES Glumes dissimilar; with lower wider than upper; exceeding apex of florets; firmer than fertile lemma. Lower glume ovate; 1 length of spikelet; coriaceous; much thinner above; without keels; keel-less except near apex; 7–11 -veined. Lower glume surface pilose. Lower glume hairs tawny. Lower glume apex truncate. Upper glume ovate; coriaceous; much thinner above; without keels; 7–11 -veined. Upper glume surface pilose. Upper glume hairs tawny. Upper glume apex obtuse, or acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; 5.5–7 mm long; hyaline; 2 -veined; pubescent; hairy above; ciliate on margins; acute. Fertile lemma oblong; 2.5–4 mm long; hyaline; 1 -veined. Lemma surface pubescent; hairy above. Lemma margins ciliate. Lemma apex lobed; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 15–20 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FLOWER Lodicules 2; oblong; fleshy; ciliate. Anthers 3; 3.5–4.5 mm long. Stigmas 2.

FRUIT Caryopsis with adherent pericarp; 2.5–2.8 mm long.

DISTRIBUTION Australasia: Australia.

NOTES Andropogoneae. Lazarides 1993.

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