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.

Thedachloa annua

HABIT Annual. Cataphylls inconspicuous. Stolons present. Culms decumbent; slender; 10–30 cm long; rooting from lower nodes. Culm-internodes 3 cm long; ridged; distally glabrous. Culm-nodes constricted. Lateral branches lacking, or sparse. Leaf-sheaths ribbed; glabrous on surface; outer margin hairy. Ligule a fringe of hairs; 0.5 mm long. Leaf-blades 1–2 cm long. Leaf-blade venation prominent. Leaf-blade surface glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; ovate; 0.3–0.5 cm long; 0.4 cm wide.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; laterally compressed; gibbous; 1.7–2.1 mm long; falling entire; readily shedding fertile florets.

GLUMES Glumes shorter than spikelet; thinner than fertile lemma. Lower glume ovate; clasping; 0.6–0.8 mm long; 0.35 length of spikelet; hyaline; without keels; 3 -veined. Lower glume lateral veins obscure. Lower glume margins ciliate. Lower glume apex obtuse. Upper glume ovate; gibbous; 1.6–1.9 length of adjacent fertile lemma; 0.85 length of spikelet; membranous; without keels; 7 -veined. Upper glume surface setose; hairy above; with tubercle-based hairs. Upper glume apex acute.

FLORETS Basal sterile florets male, or barren; with palea. Lemma of lower sterile floret similar to upper glume; elliptic; gibbous; 1 length of spikelet; membranous; 7 -veined; with unevenly spaced veins (the outer close); sulcate; acute. Palea of lower sterile floret 1.5 mm long; 0.75 length of lemma. Fertile lemma elliptic; 1 mm long; cartilaginous; light brown; shiny; without keel. Lemma surface with distinct germination flap. Lemma margins involute.

FRUIT Caryopsis with adherent pericarp; 0.8 mm long. Embryo 0.45 length of caryopsis.

DISTRIBUTION Australasia: Australia.

NOTES Paniceae. Jacobs 2007.

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