Microstegium spectabile

HABIT Annual. Culms rambling; robust; 100–170 cm long; rooting from lower nodes. Culm-nodes brown, or black; glabrous. Lateral branches ample. Leaf-sheaths outer margin glabrous, or hairy. Ligule an eciliate membrane; 1 mm long. Leaf-blades lanceolate; 10–15 cm long; 10–17 mm wide. Leaf-blade surface glabrous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 10–40; digitate; 7–10 cm long. Rhachis fragile at the nodes; ciliate on margins. Rhachis internodes linear; 2 mm long. Rhachis internode tip clavate.

Spikelets appressed; in pairs. Fertile spikelets sessile and pedicelled; 2 in the cluster. Pedicels linear; 2.5 mm long; ciliate; tip widened.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 3–4 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 elliptic; 1 length of spikelet; coriaceous; 2-keeled; keeled above. Lower glume primary vein ciliolate (above). Lower glume surface with a longitudinal median groove; impressed below. Lower glume apex obtuse. Upper glume elliptic; 1-keeled. Upper glume apex attenuate.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 0.5 mm long; hyaline; obtuse. Fertile lemma linear; 1 mm long; hyaline; without keel; 0 -veined. Lemma apex entire; acuminate; awned; 1 -awned. Principal lemma awn apical; flexuous; 4–6 mm long overall. Palea absent or minute.

FRUIT Caryopsis with adherent pericarp; obovoid; 1 mm long. Embryo 0.5 length of caryopsis.

DISTRIBUTION Asia-tropical: Malesia and Papuasia. Pacific: northwestern.

NOTES Andropogoneae. WDC 1996.

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