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.

Triodia biflora

HABIT Perennial; caespitose. Culm-internodes striate. Leaf-sheaths longer than adjacent culm internode; resinous; glabrous on surface. Leaf-sheath oral hairs bearded; 5 mm long. Ligule a fringe of hairs; 1.5–2 mm long. Leaf-blades involute; 25–30 cm long; 0.5–1.2 mm wide; coriaceous; stiff; resinous. Leaf-blade surface grooved on either side of midline; grooved abaxially. Leaf-blade margins scabrous. Leaf-blade apex pungent.

INFLORESCENCE Inflorescence a panicle.

Panicle open; elliptic; 20–25 cm long; 5–7 cm wide. Primary panicle branches simple, or sparsely divided; 8–10 cm long. Panicle axis angular. Panicle branches angular; bearded in axils.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels linear; angular; 1.5–2(–5) mm long.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 3.3–4 mm long; 2.3 mm wide; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes suppressed between florets. Floret callus obtuse.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma. Lower glume elliptic, or oblong; 2.5–3.5 mm long; 1 length of upper glume; scarious; light brown; without keels; 3 -veined. Lower glume surface asperulous. Lower glume apex truncate, or obtuse. Upper glume elliptic, or oblong; 2.5–3.5 mm long; scarious; light brown; without keels; 3 -veined. Upper glume surface asperulous. Upper glume apex truncate, or obtuse.

FLORETS Fertile lemma oblong; 3–3.8 mm long; coriaceous; much thinner above; without keel; 3 -veined. Lemma surface scaberulous; rough above. Lemma apex entire (or minutely 3-dentate); acute; muticous. Palea elliptic; cartilaginous, or coriaceous. Palea keels winged; narrowly winged; scaberulous; adorned above; with 0.5 of their length adorned. Palea surface scaberulous. Palea apex entire, or dentate; 2 -fid; obtuse. Rhachilla extension 1.3–2 mm long. Apical sterile florets 1 in number; orbicular.

FLOWER Lodicules 2; oblong; 0.3 mm long; fleshy; truncate. Anthers 3; 2 mm long.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Australasia: Australia.

NOTES Eragrostideae. Lazarides 1996.

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