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.

Leptochloa southwoodii

HABIT Annual; caespitose. Culms erect, or geniculately ascending; 137–170 cm long; 4 -noded. Culm-internodes terete; hollow; distally glabrous. Culm-nodes glabrous. Lateral branches lacking, or sparse. Leaf-sheaths striately veined; pilose; with tubercle-based hairs. Ligule an eciliate membrane; 3–5.5 mm long; lacerate. Leaf-blades 25–55 cm long; 6–12.5 mm wide. Leaf-blade surface scabrous; rough on both sides; glabrous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes numerous; borne along a central axis; ascending; unilateral; 8–17.5 cm long. Rhachis semiterete. Spikelet packing broadside to rhachis; crowded, or contiguous; regular; 2 -rowed.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 6 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 3.5–4.6 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 0.4–0.5 mm long. Floret callus glabrous, or sparsely hairy.

GLUMES Glumes persistent; shorter than spikelet. Lower glume linear, or ovate; 0.8–1.3 mm long; 0.6–0.75 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scaberulous. Lower glume lateral veins absent. Lower glume apex obtuse, or acute. Upper glume elliptic, or ovate, or obovate; 1.2–1.7 mm long; 0.8–0.9 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein scaberulous. Upper glume lateral veins absent.

FLORETS Fertile lemma elliptic, or obovate; 1.5–2 mm long; membranous; keeled; 3 -veined. Lemma midvein pubescent. Lemma lateral veins close to margins. Lemma margins pubescent. Lemma apex emarginate, or truncate, or obtuse. Palea elliptic; 1 length of lemma; 2 -veined. Palea keels puberulous. Palea surface puberulous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 0.2 mm long.

FRUIT Caryopsis ellipsoid, or obovoid; isodiametric; 0.8 mm long; rugose.

DISTRIBUTION Australasia: Australia.

NOTES Eragrostideae. Simon 2001.

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