GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Microstegium delicatulum

HABIT Annual; mat forming. Culms rambling; weak; 30–90 cm long; rooting from lower nodes. Culm-nodes bearded. Leaf-sheaths tight; smooth, or scaberulous; glabrous on surface. Ligule an eciliate membrane; 0.2–0.5 mm long. Leaf-blades elliptic; 5–10 cm long; 4–8 mm wide; flaccid. Leaf-blade surface scaberulous; pilose; sparsely hairy; hairy on both sides; with tubercle-based hairs. Leaf-blade margins scabrous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 3–5; digitate; 4–8 cm long. Rhachis fragile at the nodes; flattened; ciliate on margins. Rhachis internodes linear; 1.5 mm long. Rhachis internode tip clavate.

Spikelets appressed; in pairs. Fertile spikelets sessile and pedicelled; 2 in the cluster. Pedicels linear; flattened; 1 mm long; ciliate.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 2–2.5 mm long; falling entire; deciduous from the base, or with accessory branch structures. Spikelet callus bearded; base obtuse; attached transversely. Spikelet callus hairs 0.5 length of spikelet.

GLUMES Glumes dissimilar; firmer than fertile lemma. Lower glume oblong; 1 length of spikelet; chartaceous; 2-keeled; keeled obtusely; 4 -veined. Lower glume lateral veins obscure. Lower glume surface flat, or concave; smooth, or asperulous; rough at apex. Lower glume margins ciliate. Lower glume apex obtuse. Upper glume elliptic; 1 length of spikelet; 1-keeled. Upper glume primary vein scabrous.

FLORETS Basal sterile florets with vestigial lower floret. Fertile lemma orbicular; 0.5 mm long; hyaline; without keel; 0 -veined. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 6–8 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FLOWER Anthers 3; 1 mm long.

DISTRIBUTION Asia-temperate: China. Asia-tropical: Indo-China.

NOTES Andropogoneae. Bor 1992.

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