GrassBase - The Online World Grass Flora


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

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

Microstegium vimineum

HABIT Annual; mat forming. Culms decumbent; 10–30 cm long; rooting from lower nodes. Culm-nodes glabrous, or pubescent. Leaf-sheaths outer margin hairy. Ligule an eciliate membrane. Leaf-blades elliptic, or oblong; 5–10 cm long; 7–15 mm wide. Leaf-blade surface pubescent; hairy on both sides. Leaf-blade margins scabrous. Leaf-blade apex acute, or acuminate.

INFLORESCENCE Inflorescence composed of racemes. Peduncle pilose above.

Racemes 1–5; single, or paired, or digitate; spreading, or erect; 3–5 cm long. Central inflorescence axis 0–2.5 cm long. Rhachis fragile at the nodes; flattened; ciliate on margins. Rhachis internodes linear; 4–5 mm long.

Spikelets in pairs. Fertile spikelets sessile and pedicelled; 2 in the cluster. Pedicels linear; flattened; 3.5–4.5 mm long; ciliate.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 5.5–6.5 mm long; falling entire; deciduous from the base, or with accessory branch structures. Spikelet callus base obtuse; attached transversely.

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 lateral veins with cross-veins. Lower glume surface with a longitudinal median groove; glabrous. Lower glume apex obtuse. Upper glume elliptic; 1-keeled; 3–7 -veined. Upper glume primary vein scabrous. Upper glume muticous.

FLORETS Basal sterile florets with vestigial lower floret, or developed; barren; without significant palea. Lemma of lower sterile floret oblong; 3.5 mm long; hyaline. Fertile lemma linear; 1–1.5 mm long; hyaline; without keel. Lemma apex dentate; 2 -fid; mucronate. Palea 1 length of lemma; hyaline.

FLOWER Lodicules 2. Anthers 3; 0.3–0.5 mm long.

FRUIT Caryopsis with adherent pericarp; fusiform; 2 mm long. Embryo 0.25 length of caryopsis. Hilum punctiform.

DISTRIBUTION Africa: west-central tropical. Asia-temperate: Soviet far east, Caucasus, western Asia, China, and eastern Asia. Asia-tropical: India, Indo-China, and Malesia. North America: northeast USA and southeast USA.

NOTES Andropogoneae. Bor.

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