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.

Hemarthria vaginata

HABIT Perennial. Culms geniculately ascending; 90–180 cm long. Lateral branches ample. Ligule a ciliate membrane. Leaf-blades linear, or lanceolate; 6–50 cm long; 4–6 mm wide. Leaf-blade surface glabrous. Leaf-blade margins smooth. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes; subtended by an inflated leaf-sheath.

Racemes 1; single; smoothly terete; 10–20 cm long. Rhachis fracturing into irregular segments; flattened; glabrous on margins. Rhachis internodes columnar; 4.5–5.2 mm long; adherent to upper glume of sessile spikelet. Rhachis internode tip oblique; flat.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels fused to internode; united wholly; oblong; flattened; 3.5–4.5 mm long; tip rectangular.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; lanceolate; 6–7 mm long; as long as fertile; deciduous with the fertile. Companion sterile spikelet callus truncate. Companion sterile spikelet glumes herbaceous; acuminate; muticous, or awned; one glume awned; with 0–4 mm long awn. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 6–7 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate; glabrous; base truncate; attached obliquely.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; herbaceous; 2-keeled; keeled laterally; winged on keel; winged narrowly. Lower glume intercarinal veins distinct. Lower glume surface flat. Lower glume apex acute, or acuminate. Upper glume elliptic; membranous; without keels; 3 -veined. Upper glume apex attenuate; muticous, or awned; 1 -awned. Upper glume awn 0–4 mm long.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 4.5–7 mm long; hyaline; obtuse. Fertile lemma oblong; 1.5–1.7 mm long; hyaline; without keel; 0 -veined. Lemma apex obtuse. Palea absent or minute.

FLOWER Anthers 3.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Asia-temperate: China. Asia-tropical: India, Indo-China, and Malesia.

NOTES Andropogoneae. Fl Assam 1993.

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