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.

Plagiosetum

HABIT Annual. Culms erect, or decumbent; 20–50 cm long; rooting from lower nodes. Ligule a fringe of hairs.

INFLORESCENCE Inflorescence composed of racemes.

Racemes borne along a central axis; spreading, or deflexed; cuneate; unilateral; bearing 1 spikelet, or few fertile spikelets; bearing 1–2 fertile spikelets on each. Central inflorescence axis flattened; tip filiform. Rhachis deciduous from axis; flattened; terminating in a barren extension; extension a fan of bristles. Raceme-bases linear.

Spikelets subtended by an involucre. Fertile spikelets pedicelled; 1 in the cluster. Involucre composed of bristles. Involucral bristles deciduous with the fertile spikelets; numerous. Pedicels oblong.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 6–7.5 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes reaching apex of florets; thinner than fertile lemma. Lower glume ovate; membranous; without keels; 5–7 -veined. Lower glume surface without pits. Lower glume apex acute, or acuminate. Upper glume lanceolate; membranous; without keels; 15–19 -veined. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; membranous; 15–19 -veined; acute. Fertile lemma elliptic; dorsally compressed; indurate; without keel; wingless. Lemma surface rugulose; without grooves. Lemma margins involute. Lemma apex acute.

FLOWER Anthers 3.

FRUIT Caryopsis with adherent pericarp. Embryo 0.5–0.66 length of caryopsis. Hilum elliptic.

DISTRIBUTION Australasia.

Please cite this publication as detailed in How to Cite Version: 27th January 2014.