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.

Myriostachya wightiana

HABIT Perennial; caespitose; clumped densely. Butt sheaths scarious; glabrous. Basal innovations intravaginal; flabellate. Culms erect; 100–150 cm long. Culm-internodes elliptical in section. Leaves mostly basal. Leaf-sheaths as wide as blade at the collar; keeled; smooth; glabrous on surface. Ligule a fringe of hairs; 0.5 mm long. Leaf-blades 45–60 cm long; 10–20 mm wide. Leaf-blade surface smooth. Leaf-blade margins smooth. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes numerous; borne along a central axis; closely spaced; in a multilateral false spike; spreading; oblong; unilateral; 2–8 cm long. Central inflorescence axis 25–60 cm long. Rhachis deciduous from axis; subterete; puberulous on surface. Spikelet packing broadside to rhachis.

Spikelets ascending; solitary. Fertile spikelets pedicelled. Pedicels linear; 1.5–2 mm long.

FERTILE SPIKELETS Spikelets comprising 2–12 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 5–12 mm long; falling entire; deciduous with the pedicel; pedicel base truncate. Rhachilla internodes eventually visible between lemmas.

GLUMES Glumes similar; shorter than spikelet; gaping. Lower glume lanceolate; 0.7–1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acuminate; awned. Lower glume awn 1–5 mm long. Upper glume lanceolate; 0.5–0.7 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume apex acuminate; awned. Upper glume awn 1–3 mm long.

FLORETS Fertile lemma ovate; laterally compressed; 2.5–3.5 mm long; membranous; keeled; 3 -veined. Lemma lateral veins obscure. Lemma apex acute; mucronate. Palea oblong; 1 length of lemma; 2 -veined. Palea keels ciliolate. Palea apex entire; acute. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; fleshy; truncate. Anthers 3; linear; 1 mm long. Stigmas 2.

FRUIT Caryopsis with adherent pericarp; ovoid; laterally compressed. Embryo 0.4 length of caryopsis. Disseminule comprising a spikelet.

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

NOTES Eragrostideae. WDC.

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