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.

Digitaria killeenii

HABIT Annual. Butt sheaths persistent and investing base of culm; with fibrous dead sheaths. Culms erect; robust; 180–200 cm long; 3.5–4 mm diam. Culm-internodes distally glabrous. Culm-nodes brown; glabrous. Lateral branches ample; arising from mid culm. Leaves cauline. Leaf-sheaths 22–29 cm long; longer than adjacent culm internode. Ligule an eciliate membrane; 1.5 mm long. Leaf-blades 58–75 cm long; 8–13 mm wide; 6–55 cm long at summit of culm. Leaf-blade surface glabrous.

INFLORESCENCE Inflorescence composed of racemes. Peduncle glabrous.

Racemes 4–9; digitate; unilateral; 4–9 cm long. Rhachis narrowly winged; angular; 1–1.5 mm wide; scabrous on margins.

Spikelets in threes, or clustered at each node. Fertile spikelets pedicelled; 3–5 in the cluster. Pedicels unequal; 0.5–5 mm long; scabrous; glabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic, or obovate; dorsally compressed; 3–3.2 mm long; 1.3–1.4 mm wide; falling entire.

GLUMES Glumes one the lower absent or obscure, or two; shorter than spikelet; thinner than fertile lemma. Lower glume oblate; 0.1–0.2 mm long; hyaline. Lower glume apex truncate. Upper glume elliptic; 2.5–3.8 mm long; membranous; without keels; (3–)5 -veined. Upper glume lateral veins prominent. Upper glume surface pubescent; hairy between veins; with clavate hairs. Upper glume margins ciliolate.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret elliptic; 2.8–3 mm long; 1 length of spikelet; membranous; 7 -veined; prominently veined; pilose; hairy between veins; with clavate hairs; ciliolate on margins. Palea of lower sterile floret 0.5 mm long. Fertile lemma elliptic; 2.8–3 mm long; cartilaginous; much thinner on margins; purple, or black; without keel. Lemma margins flat; covering most of palea. Lemma apex apiculate. Palea cartilaginous.

FLOWER Lodicules 2; 0.7 mm long. Anthers 3; 1.5 mm long.

FRUIT Caryopsis with adherent pericarp; ellipsoid; 2–2.2 mm long. Embryo 0.33 length of caryopsis. Hilum elliptic.

DISTRIBUTION South America: western South America.

NOTES Paniceae. FTEA.

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