Danthonia rugoloana

HABIT Perennial; caespitose; clumped densely. Rhizomes short. Culms erect; 4–16 cm long; 1 -noded. Culm-nodes glabrous, or pubescent. Leaf-sheaths striately veined; glabrous on surface, or pilose. Ligule a fringe of hairs; 0.3–0.6 mm long. Leaf-blades curved; filiform; involute; 0.3–0.6 cm long; 0.5–1 mm wide. Leaf-blade surface scaberulous; rough abaxially; pilose; hairy adaxially. Leaf-blade apex acute; hooded.

INFLORESCENCE Inflorescence comprising only a few spikelets; comprising 1–3 fertile spikelets; bracteate at pedicel base. Peduncle hirsute above.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 2–8 mm long; ciliate.

FERTILE SPIKELETS Spikelets comprising 4–6 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 10–14 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 0.4–0.7 mm long; pilose; truncate, or obtuse. Floret callus hairs 1–2.5 mm long.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 10–14 mm long; 1 length of upper glume; membranous; much thinner on margins; without keels; 3–7 -veined. Lower glume lateral veins obscure. Lower glume surface smooth, or asperulous; rough on veins. Lower glume apex acute, or acuminate. Upper glume lanceolate; 10–14 mm long; 1.6–2 length of adjacent fertile lemma; membranous; with hyaline margins; without keels; 3–7 -veined. Upper glume lateral veins obscure. Upper glume surface smooth, or asperulous; rough on veins. Upper glume apex acute, or acuminate.

FLORETS Fertile lemma elliptic; 6–7.6 mm long; coriaceous; much thinner on margins; without keel; 7–9(–11) -veined. Lemma midvein ciliate. Lemma surface pilose; hairy below. Lemma margins ciliate. Lemma hairs 1–2.3 mm long. Lemma apex lobed; 2 -fid; with lobes 3–4.5 mm long; incised 0.5–0.6 of lemma length; awned; 3 -awned. Principal lemma awn from a sinus; geniculate; flat below; 5.5–7.5 mm long overall; with twisted column. Lateral lemma awns arising on apex of lobes; 0.5–2 mm long. Palea elliptic; 3.7–5 mm long; 2 -veined. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; 0.4–0.7 mm long; fleshy; ciliate. Anthers 3; 0.2–0.5 mm long; retained within floret.

FRUIT Caryopsis with adherent pericarp; ellipsoid; 1.7–2.3 mm long; light brown. Embryo 0.5 length of caryopsis. Hilum elliptic; 0.33 length of caryopsis.

CLEISTOGENES AND VIVIPARY Cleistogenes present; in lower sheaths; 1 -flowered; 4.5 mm long.

DISTRIBUTION South America: southern South America.

NOTES Arundineae. Sulecik 2005.

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