Monocymbium deightonii

HABIT Perennial. Culms decumbent, or prostrate; slender; 30–120 cm long; 0.5–1.7 mm diam.; rooting from lower nodes. Leaf-sheaths glabrous on surface, or pilose. Ligule an eciliate membrane. Leaf-blades lanceolate; 1–5 cm long; 2–7 mm wide. Leaf-blade surface glabrous, or pilose; sparsely hairy; hairy abaxially. Leaf-blade margins cartilaginous; ciliate. Leaf-blade apex acute.

INFLORESCENCE Synflorescence compound; scanty; 8–30 cm long. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; enclosed. Spatheole lanceolate; 1.5–2.7 cm long; membranous; brown, or red; glabrous. Peduncle 0.4–0.8 cm long; pilose above.

Racemes 1; single; unilateral; 0.8–1.6 cm long; bearing few fertile spikelets. Rhachis fragile at the nodes; ciliate on margins. Spikelet packing crowded. Rhachis internodes filiform; 1.3–1.8 mm long. Rhachis internode tip oblique.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels filiform; 1.3–1.8 mm long; ciliate.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; lanceolate, or elliptic; dorsally compressed; 2.5–3.3 mm long; as long as fertile; separately deciduous. Companion sterile spikelet callus cuneate; 0.3 mm long; obtuse. Companion sterile spikelet glumes coriaceous; 10 -veined; glabrous; muticous. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic, or oblong; dorsally compressed; obtuse; 3–3.7 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus square; pilose; hairy on the sides; base obtuse; attached obliquely. Spikelet callus hairs 1 mm long.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma; shiny. Lower glume elliptic; 1 length of spikelet; coriaceous; yellow, or dark brown; without keels; keel-less except near apex; 9–10 -veined. Lower glume surface scabrous; rough at apex; glabrous. Lower glume apex entire; truncate. Upper glume elliptic; chartaceous; without keels; keel-less except near apex; 3 -veined. Upper glume surface scabrous; rough at apex. Upper glume margins ciliolate. Upper glume apex dentate; 2 -fid; awned; 1 -awned. Upper glume awn 1–2 mm long.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; hyaline; 0 -veined; without midvein; without lateral veins; ciliate on margins. Fertile lemma linear; 2.5–2.8 mm long; hyaline; without keel. Lemma apex lobed; 2 -fid; incised 0.4–0.6 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 9–13 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FLOWER Anthers 3; 1–1.5 mm long.

DISTRIBUTION Africa: west tropical.

NOTES Andropogoneae. FWTA.

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