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 fissura

HABIT Perennial; caespitose; clumped densely. Culms 50–70 cm long. Leaf-sheaths smooth; glabrous on surface; outer margin hairy. Leaf-sheath oral hairs bearded; 2–4 mm long. Ligule a fringe of hairs; 0.2–0.3 mm long. Leaf-blade base with a brief petiole-like connection to sheath; petiole 0.4–0.6 cm long. Leaf-blades spreading, or reflexed; aciculate; conduplicate; 4.5–7 cm long; 1–1.5 mm wide; coriaceous; stiff; resinous. Leaf-blade surface glabrous. Leaf-blade apex pungent.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; unilateral; 15–20 cm long; 5–10 mm wide. Spikelet packing broadside to rhachis; 0.4–0.6 their length apart; regular; 2 -rowed.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 8–16 fertile florets; with diminished florets at the apex. Spikelets lanceolate, or oblong; laterally compressed; 12–17 mm long; 4–4.6 mm wide; breaking up at maturity; disarticulating below each fertile floret. Floret callus brief; 0.3 mm long; bearded; obtuse. Floret callus hairs 2–3 mm long.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume ovate; 3.5–4 mm long; 1 length of upper glume; scarious, or cartilaginous, or coriaceous; without keels; 3 -veined. Lower glume surface glabrous. Lower glume apex obtuse, or acute; mucronate. Upper glume ovate; 3.5–4 mm long; 0.8 length of adjacent fertile lemma; chartaceous, or cartilaginous, or coriaceous; without keels; 3 -veined. Upper glume surface glabrous. Upper glume apex obtuse, or acute; mucronate.

FLORETS Fertile lemma lanceolate, or ovate; 4.5–5 mm long; cartilaginous, or coriaceous; much thinner on margins; without keel; 9 -veined. Lemma midvein eciliate. Lemma lateral veins with distinct primaries but obscure intermediates. Lemma apex acuminate; mucronate. Palea lanceolate; 0.8–1 length of lemma; 3 -veined. Palea keels wingless; eciliate. Palea apex emarginate, or acute. Apical sterile florets resembling fertile though underdeveloped.

DISTRIBUTION Australasia: Australia.

NOTES Eragrostideae. Fl Australia 2006.

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