Sorghum matarankense

HABIT Annual. Culms erect, or geniculately ascending; 100–200 cm long; without nodal roots, or with prop roots. Culm-internodes distally pruinose. Culm-nodes constricted; glabrous, or pubescent. Lateral branches lacking, or sparse. Leaf-sheaths glabrous on surface. Leaf-sheath oral hairs lacking, or pubescent, or ciliate. Leaf-sheath auricles erect. Ligule an eciliate membrane, or a ciliolate membrane; 2–3 mm long. Leaf-blades 5–70 mm wide.

INFLORESCENCE Inflorescence a panicle with branches tipped by a raceme.

Panicle open; dense; 30–40 cm long. Primary panicle branches whorled at most nodes; sparsely divided; 4.5–8 cm long. Panicle axis terete, or angular.

Racemes 1.5–3 cm long; bearing few fertile spikelets; bearing 2–4 fertile spikelets on each. Rhachis fragile at the nodes; ciliate on margins. Rhachis internodes linear. Rhachis internode tip oblique.

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; 4.5–7.3 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; 7 -veined; acute, or acuminate; muticous. Companion sterile spikelet lemmas enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate, or elliptic; dorsally compressed; 4.5–6 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus brief, or square; 0.5–0.7 mm long; base obtuse.

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; 2-keeled; keeled above; 7–9 -veined. Lower glume surface pilose. Lower glume apex dentate; 2 -fid; mucronate. Upper glume ovate; coriaceous; much thinner above; 1-keeled; keeled above; 5–7 -veined. Upper glume surface pilose. Upper glume apex dentate; 2 -fid.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; 4.5–6 mm long; hyaline; 2 -veined; acute. Fertile lemma oblong; 4–5 mm long; hyaline; 1 -veined. Lemma apex lobed; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 30–40 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FLOWER Lodicules 2; oblong; fleshy; ciliate; hairy on the corners. Anthers 3; 2.5–3 mm long. Stigmas 2. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; 2–3 mm long.

DISTRIBUTION Australasia: Australia.

NOTES Andropogoneae. Lazarides 1993.

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