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.

Plagiosetum refractum

HABIT Annual. Culms erect, or decumbent; 20–50 cm long; rooting from lower nodes. Ligule a fringe of hairs; 1 mm long. Leaf-blades convolute; 2–10 cm long; 2–5 mm wide. Leaf-blade surface scabrous; rough on both sides. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 5–15; borne along a central axis; deflexed, or spreading; cuneate; unilateral; 1–3 cm long; bearing 1 spikelet, or few fertile spikelets; bearing 1–2 fertile spikelets on each. Central inflorescence axis 10–20 cm long; flattened; tip filiform. Rhachis deciduous from axis; flattened; terminating in a barren extension; extension a fan of bristles. Raceme-bases linear; 1–8 mm long.

Spikelets subtended by an involucre. Fertile spikelets pedicelled; 1 in the cluster. Involucre composed of bristles; 7–15 mm long. Involucral bristles deciduous with the fertile spikelets; numerous; 3–4 per spikelet. Pedicels oblong; 1.5–4 mm long.

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

GLUMES Glumes similar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.5–0.66 length of spikelet; membranous; without keels; 5–7 -veined. 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 similar to upper glume; lanceolate; 1 length of spikelet; membranous; 15–19 -veined; acute. Fertile lemma elliptic; dorsally compressed; 5 mm long; indurate; without keel. Lemma surface rugulose. Lemma margins involute. Lemma apex acute.

FLOWER Anthers 3; 2.25 mm long.

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

DISTRIBUTION Australasia: Australia.

NOTES Paniceae. Vickery.

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