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.

Psammagrostis wiseana

HABIT Annual. Butt sheaths pubescent. Culms decumbent, or prostrate; 4–35 cm long (long). Leaf-sheaths inflated. Ligule a fringe of hairs. Leaf-blades 0.3–3.5 cm long; 1–2 mm wide. Leaf-blade surface ribbed. Leaf-blade apex acute.

INFLORESCENCE Inflorescence composed of racemes, or comprising only a few spikelets; terminal and axillary; deciduous as a whole; subtended by a spatheole; embraced at base by subtending leaf. Spatheole lanceolate; 0.3–1 cm long; herbaceous. Peduncle straight, or nodding; widened at apex; disarticulating; disarticulating above uppermost sheath; base blunt.

Racemes 1; single; unilateral; 0.5–1 cm long; bearing 1 spikelet, or few fertile spikelets; bearing 1–3 fertile spikelets on each. Rhachis flattened.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 3–7 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 4–8.5 mm long; falling entire; deciduous with accessory branch structures. Rhachilla internodes clavate; 1–2 mm long.

GLUMES Glumes dissimilar; shorter than spikelet; similar to fertile lemma in texture. Lower glume lanceolate; 2.5 mm long; 0.9–1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 2.5–3 mm long; 1.1–1.3 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma oblong; 2.2–2.3 mm long; membranous; keeled; 3 -veined. Lemma lateral veins ribbed. Lemma apex obtuse; mucronate. Palea bowed outwards; 1 length of lemma; 2 -veined. Palea keels scaberulous. Palea apex truncate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 0.5–0.6 mm long.

FRUIT Caryopsis with free soft pericarp; oblong; trigonous; 1 mm long. Embryo 0.33 length of caryopsis. Hilum punctiform.

DISTRIBUTION Australasia: Australia.

NOTES Eragrostideae. CEH.

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