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.

Cortaderia atacamensis

HABIT Perennial; caespitose. Culms erect; robust; 200–300 cm long; 2.5–3.5 mm diam. Culm-nodes brown; glabrous. Ligule a fringe of hairs; 1–2 mm long. Leaf-blades 50–60 cm long; 5–7 mm wide. Leaf-blade midrib keeled beneath. Leaf-blade surface scabrous. Leaf-blade margins scabrous.

INFLORESCENCE Gynodioecious ("male", in this context, indicating the bisexual state). Inflorescence a panicle; embraced at base by subtending leaf. Peduncle 50 cm long.

Panicle open; oblong; dense; 40–50 cm long; 10–14 cm wide. Primary panicle branches appressed; 15–20 cm long. Panicle axis scabrous; pilose. Panicle branches capillary.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 2–3 mm long; scabrous.

FERTILE SPIKELETS Spikelets comprising 4 fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; 11–12 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1–1.5 mm long. Floret callus evident; 0.5 mm long; pilose.

GLUMES Glumes similar; shorter than spikelet; similar to fertile lemma in texture. Lower glume lanceolate; 7–8 mm long; 0.8 length of upper glume; hyaline; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume surface asperulous. Lower glume margins ciliolate. Lower glume apex entire, or dentate; 2 -fid; acuminate. Upper glume lanceolate; 8.5–9.5 mm long; 1 length of adjacent fertile lemma; hyaline; without keels; 1 -veined. Upper glume lateral veins absent. Upper glume surface asperulous. Upper glume margins ciliolate. Upper glume apex entire, or dentate; 2 -fid; acuminate.

FLORETS Fertile florets female. Fertile lemma lanceolate; 8.5–9.5 mm long; hyaline; without keel; 3 -veined. Lemma surface scaberulous; plumose; hairy below. Lemma margins ciliolate. Lemma hairs 4.5–5.5 mm long. Lemma apex attenuate. Palea 3.5–4 mm long; 0.3–0.4 length of lemma; hyaline; 2 -veined. Palea keels ciliolate. Palea surface pilose; hairy on flanks. Palea apex truncate, or obtuse. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; fleshy; ciliate. Anthers 3. Staminodes present; 0.2 mm long.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: western South America and southern South America.

NOTES Arundineae. Conert 1993.

ADDITIONAL CHARACTERS Bisexual plants unknown.

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