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.

Echinochloa lacunaria

HABIT Annual. Butt sheaths papery. Culms erect; slender; 45–90 cm long; 4 -noded. Culm-internodes ridged; smooth. Culm-nodes glabrous. Leaf-sheaths loose; keeled; smooth; glabrous on surface. Ligule absent. Leaf-blades 10–25 cm long; 5–7 mm wide. Leaf-blade venation with 6 secondary veins. Leaf-blade surface smooth; glabrous. Leaf-blade margins cartilaginous; smooth. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes few; borne along a central axis; erect; unilateral; 2–6 cm long; simple, or with branchlets at base of longer racemes. Rhachis narrowly winged; angular; smooth on margins. Spikelet packing lax; 4 -rowed. Raceme-bases glabrous.

Spikelets in pairs. Fertile spikelets pedicelled; subequal. Pedicels unequal; glabrous; tip discoid.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic, or ovate; dorsally compressed; turgidly plano-convex; acute; 4.75–6 mm long; 2 mm wide; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; clasping; 0.33–0.5 length of spikelet; without keels; 3–5 -veined. Lower glume surface smooth, or asperulous. Lower glume apex acute, or acuminate. Upper glume elliptic; gibbous; 1 length of spikelet; membranous; without keels; 5 -veined. Upper glume surface asperulous; rough above. Upper glume apex acuminate, or cuspidate.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret similar to upper glume; elliptic; 1 length of spikelet; membranous; 5–7 -veined; concave across back; scaberulous; rough above; acuminate, or cuspidate. Fertile lemma elliptic, or ovate; gibbous; 4 mm long; 2 mm wide; indurate; much thinner above; yellow; shiny; without keel; 5 -veined. Lemma lateral veins obscure. Lemma surface smooth. Lemma margins involute. Lemma apex cuspidate. Palea reflexed at apex; 1 length of lemma; indurate.

FLOWER Anthers 3; 1.1–1.3 mm long; brown.

FRUIT Caryopsis with adherent pericarp; ellipsoid, or oblong; 2.2–2.3 mm long. Embryo 0.75 length of caryopsis.

DISTRIBUTION Australasia: Australia.

NOTES Paniceae. Fl NSW 1997.

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