Microstegium steenisii

HABIT Annual. Culms geniculately ascending; 50–80 cm long; rooting from lower nodes. Culm-internodes distally glabrous. Culm-nodes pubescent. Lateral branches sparse. Leaf-sheaths 2–7 cm long; mostly shorter than adjacent culm internode; glabrous on surface. Ligule a ciliolate membrane; 0.5–0.7 mm long. Leaf-blades lanceolate; 4–5 cm long; 6–8 mm wide. Leaf-blade surface glabrous, or pubescent.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2–4; digitate; 4–5 cm long. Rhachis fragile at the nodes; ciliate on margins. Rhachis hairs 1–1.5 mm long. Rhachis internodes linear.

Spikelets in pairs. Fertile spikelets sessile and pedicelled; 2 in the cluster; subequal. Pedicels linear; ciliate.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 5 mm long; falling entire; deciduous from the base and with accessory branch structures. Spikelet callus pilose; base obtuse; attached transversely. Spikelet callus hairs 1–1.5 mm long.

GLUMES Glumes dissimilar; firmer than fertile lemma. Lower glume elliptic; 1 length of spikelet; coriaceous; 2-keeled; keeled obtusely; 4 -veined. Lower glume primary vein scabrous. Lower glume surface concave; glabrous. Lower glume margins ciliate. Lower glume apex emarginate. Upper glume elliptic; 1-keeled; 3 -veined. Upper glume margins ciliate. Upper glume apex acute; muticous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; 5 mm long; hyaline. Fertile lemma lanceolate; 2 mm long; hyaline; without keel; 0 -veined. Lemma apex lobed; 2 -fid; incised 0.25 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; flexuous; 12–15 mm long overall. Palea oblong; 0.33 length of lemma.

FLOWER Anthers 3; 1.5 mm long.

DISTRIBUTION Asia-tropical: Malesia.

NOTES Andropogoneae. Fl Java 1997.

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