Microstegium tenue

HABIT Annual. Culms rambling; 20–100 cm long; rooting from lower nodes. Ligule an eciliate membrane. Leaf-blades linear, or lanceolate; 4–20 cm long; 4–8 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2–4; digitate; 2–5 cm long. Rhachis fragile at the nodes; ciliate on margins. Rhachis internodes pyriform; 1.5–2 mm long.

Spikelets in pairs. Fertile spikelets sessile and pedicelled; 2 in the cluster; the upper smaller. Pedicels clavate; 1.5 mm long; ciliate.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 2–3 mm long; falling entire; deciduous from the base and with accessory branch structures. Spikelet callus pubescent; base obtuse; attached transversely.

GLUMES Glumes dissimilar; firmer than fertile lemma. Lower glume oblong; 1 length of spikelet; coriaceous; 2-keeled; keeled obtusely. Lower glume surface with a longitudinal median groove; puberulous; hairy at apex. Lower glume apex emarginate. Upper glume elliptic; 1-keeled. Upper glume apex acute; awned; 1 -awned. Upper glume awn 1–3 mm long.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; 1.5 mm long; hyaline. Fertile lemma lanceolate; 0.3 mm long; hyaline; without keel; 0 -veined. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 8–12 mm long overall; with twisted column. Palea absent or minute.

DISTRIBUTION Asia-tropical: Malesia. Pacific: northwestern.

NOTES Andropogoneae. WDC 1997.

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