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.

Tristachya superba

HABIT Perennial; caespitose. Rhizomes short. Butt sheaths thickened and forming a bulb; pubescent, or woolly. Culms erect; 120–240 cm long. Ligule a fringe of hairs. Leaf-blades 30–60 cm long; 5–12 mm wide; glaucous.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; linear; 20–40 cm long. Panicle branches glabrous, or villous.

Spikelets in threes, or in pairs (rarely). Fertile spikelets pedicelled; (2–)3 in the cluster. Pedicels free; filiform, or linear; unequal; 2–60 mm long.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; compressed slightly; 25–35 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; 3 mm long; pubescent (rufously); pungent.

GLUMES Glumes persistent; dissimilar; exceeding apex of florets. Lower glume elliptic; 0.5 length of spikelet; chartaceous; dark brown; without keels; 3 -veined. Lower glume surface glabrous, or pilose (rarely). Lower glume apex acute. Upper glume lanceolate; 1 length of spikelet; chartaceous; dark brown; without keels; 3 -veined. Upper glume surface glabrous. Upper glume apex acute.

FLORETS Basal sterile florets male; with palea; separately deciduous. Lemma of lower sterile floret similar to upper glume; lanceolate; 1 length of spikelet; chartaceous; 5–7 -veined; acute. Fertile lemma oblong; 10–13 mm long; coriaceous; without keel; 7 -veined. Lemma surface pubescent. Lemma margins involute; interlocking with palea keels. Lemma apex lobed; 2 -fid; with lanceolate lobes; incised 0.2–0.3 of lemma length; acute; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; subterete below; 40–120 mm long overall; with twisted column; deciduous; abscissing from top of lemma. Palea 2 -veined. Palea keels approximate; thickened.

FLOWER Anthers 3. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; glabrous.

DISTRIBUTION Africa: west tropical, west-central tropical, northeast tropical, east tropical, southern tropical, and south.

NOTES Arundinelleae. FTEA.

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