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.

Triodia compacta

HABIT Perennial; caespitose. Butt sheaths coriaceous, or indurate; distinctly ribbed. Culms 50–120 cm long. Culm-internodes smooth. Leaf-sheaths longer than adjacent culm internode; scaberulous; glabrous on surface; outer margin glabrous, or hairy. Leaf-sheath oral hairs pubescent. Ligule a fringe of hairs; 0.2–0.3 mm long. Leaf-blades filiform; conduplicate; 3.5–13 cm long; 0.8–1.3 mm wide; coriaceous; stiff; without exudate. Leaf-blade surface scabrous; rough adaxially. Leaf-blade apex pungent.

INFLORESCENCE Inflorescence a panicle; exserted, or embraced at base by subtending leaf.

Panicle open; linear, or oblong; dense; 3.9–26 cm long; 1–2 cm wide. Primary panicle branches indistinct the panicle almost racemose, or simple. Panicle branches terete, or angular, or flat; smooth, or scaberulous.

Spikelets solitary, or in pairs. Fertile spikelets pedicelled. Pedicels 3–15 mm long.

FERTILE SPIKELETS Spikelets comprising 6–13 fertile florets; with diminished florets at the apex. Spikelets lanceolate, or elliptic, or oblong, or ovate; laterally compressed; 11–24 mm long; 3–9 mm wide; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes thickened; 1–1.3 mm long; smooth, or scaberulous. Floret callus straight, or curved; glabrous, or pubescent; obtuse.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma. Lower glume linear, or ovate; 8.5–13 mm long; 1 length of upper glume; coriaceous; 1-keeled; 3–5 -veined. Lower glume lateral veins obscure. Lower glume surface asperulous; rough above. Lower glume apex acute, or acuminate. Upper glume linear, or ovate; 8.5–13 mm long; coriaceous; 1-keeled; keeled all along, or above; 3–5 -veined. Upper glume lateral veins obscure. Upper glume surface asperulous; rough above. Upper glume apex acute, or acuminate.

FLORETS Fertile lemma elliptic, or obovate; 7–11 mm long; coriaceous; much thinner on margins; keeled; keeled all along, or above; 9 -veined. Lemma midvein pubescent. Lemma lateral veins in close groups. Lemma surface scaberulous; rough above; glabrous, or pubescent; hairy below; inner surface pubescent. Lemma margins pubescent. Lemma apex dentate; 2 -fid; obtuse; muticous, or mucronate. Palea lanceolate, or elliptic; 0.5–0.9 length of lemma; scarious, or coriaceous. Palea keels thickened; scabrous. Palea surface glabrous, or pubescent; hairy below. Palea apex emarginate, or obtuse. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; 0.5 mm long; fleshy. Anthers 3; 2–4 mm long.

FRUIT Caryopsis with adherent pericarp; sulcate on hilar side; 3 mm long.

DISTRIBUTION Australasia: Australia.

NOTES Eragrostideae. Lazarides 1996.

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