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.

Chionochloa rigida

HABIT Perennial; caespitose; clumped densely. Butt sheaths dark brown; persistent and investing base of culm; with dead sheaths fracturing into segments. Basal innovations intravaginal; flabellate. Culms erect; 100–150 cm long. Culm-internodes distally glabrous, or hirsute. Culm-nodes glabrous. Leaves mostly basal. Leaf-sheaths 10–30 cm long; keeled; pubescent, or pilose; inner surface glabrous. Leaf-sheath oral hairs pubescent; 2 mm long. Ligule a fringe of hairs; 2 mm long. Leaf-blades deciduous with part of sheath attached; 40–80 cm long; 4–7 mm wide; coriaceous; stiff; glaucous. Leaf-blade surface scabrous; rough abaxially; glabrous; hairless except near base. Leaf-blade margins cartilaginous; ciliate; hairy at base. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; 10–30 cm long. Panicle branches scaberulous; glabrous, or pilose; bearded in axils; with prominent pulvini.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 6–8 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 15–20 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1.5 mm long. Floret callus elongated; 1.5 mm long; bearded; disarticulating obliquely. Floret callus hairs 3.5 mm long.

GLUMES Glumes persistent; similar; shorter than spikelet; similar to fertile lemma in texture. Lower glume lanceolate; 12–14 mm long; 0.9 length of upper glume; membranous; without keels; 1–3 -veined. Lower glume lateral veins absent, or obscure. Lower glume apex acute, or setaceously attenuate. Upper glume lanceolate; 14–16 mm long; 1.6 length of adjacent fertile lemma; membranous; without keels; 5–7 -veined. Upper glume apex acute, or setaceously attenuate.

FLORETS Fertile lemma elliptic; 9–10 mm long; membranous; without keel; 7 -veined. Lemma surface pilose. Lemma margins ciliate. Lemma apex lobed; 2 -fid; with simple equal lobes, or with lateral lobes bidentate; with triangular lobes; with lobes 3 mm long; incised 0.33 of lemma length; awned; 1 -awned, or 3 -awned. Principal lemma awn from a sinus; geniculate; flat below; 10–16 mm long overall; with twisted column. Column of lemma awn 2–4 mm long. Lateral lemma awns arising on apex of lobes, or between lobes (when bidentate); 0–3.5 mm long; shorter than principal. Palea 8.5 mm long. Palea keels ciliolate. Palea surface pilose; hairy on flanks. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; 0.75 mm long; membranous; veined; ciliate. Anthers 4.5–5 mm long.

FRUIT Caryopsis with adherent pericarp; 3.5 mm long. Hilum linear.

DISTRIBUTION Australasia: New Zealand.

NOTES Arundineae. Connor.

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