Danthonia araucana

HABIT Perennial. Basal innovations intravaginal. Culms erect; 6–40 cm long; 2–4 -noded. Leaf-sheaths pilose. Leaf-sheath oral hairs ciliate; 3 mm long. Ligule a fringe of hairs; 0.2–1 mm long. Leaf-blades 4–8 cm long; 1–2 mm wide. Leaf-blade surface pilose; sparsely hairy, or moderately hairy.

INFLORESCENCE Inflorescence a panicle, or comprising only a few spikelets; comprising 2–8 fertile spikelets. Peduncle glabrous.

Panicle open; linear; 1.4–6.8 cm long; bearing few spikelets.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 0.5–12 mm long; pubescent.

FERTILE SPIKELETS Spikelets comprising 4–8 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 12–19 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 0.3–0.8 mm long; glabrous. Floret callus evident; 0.7–1 mm long; pubescent, or pilose. Floret callus hairs 0.3–1.5 mm long.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 7–14 mm long; 1 length of upper glume; membranous; much thinner on margins; mid-green, or purple; without keels; 5 -veined. Lower glume apex acuminate. Upper glume lanceolate; 7–14 mm long; 1–1.5 length of adjacent fertile lemma; membranous; with hyaline margins; mid-green, or purple; without keels; 5 -veined. Upper glume apex acuminate.

FLORETS Fertile lemma elliptic; 7–9.5 mm long; chartaceous; without keel. Lemma surface pubescent; hairy below. Lemma margins ciliate; hairy in the middle. Lemma hairs 0.8–1.5 mm long. Lemma apex lobed; 2 -fid; with lobes 2.8–5 mm long; awned; 3 -awned. Principal lemma awn from a sinus; geniculate; 6–11 mm long overall; with twisted column. Lateral lemma awns arising on apex of lobes; 0.5–2.5 mm long; shorter than principal. Palea lanceolate; 4–5.5 mm long; 2 -veined. Palea surface pilose; hairy on back. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; 0.5–0.8 mm long; fleshy; glabrous. Anthers 3; 1.5–3 mm long; retained within floret, or eventually exserted.

FRUIT Caryopsis with adherent pericarp; ellipsoid; 1.6–2.5 mm long; light brown. Embryo 0.4 length of caryopsis. Hilum linear; 0.3 length of caryopsis.

CLEISTOGENES AND VIVIPARY Cleistogenes present; in upper sheaths and in lower sheaths.

DISTRIBUTION South America: southern South America.

NOTES Arundineae. Baezu 1997.

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