Cortaderia sericantha

HABIT Perennial; caespitose. Butt sheaths persistent and investing base of culm; with fibrous dead sheaths. Culms 30–50 cm long; 1 mm diam. Culm-nodes glabrous. Lateral branches lacking. Leaf-sheaths glabrous on surface. Leaf-sheath oral hairs bearded. Ligule a fringe of hairs; 1–1.5 mm long. Leaf-blades convolute; 10–25 cm long; 2–3 mm wide. Leaf-blade surface pilose; hairy adaxially, or on both sides. Leaf-blade margins scabrous.

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

Panicle contracted; elliptic; 4–10 cm long; 2–3 cm wide. Primary panicle branches 5 cm long. Panicle axis pilose. Panicle branches pilose.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 2–4 mm long; ciliate.

FERTILE SPIKELETS Spikelets comprising 2–3 fertile florets; with diminished florets at the apex. Spikelets cuneate; laterally compressed; 17–22 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 1.5 mm long; bearded. Floret callus hairs 2–3 mm long.

GLUMES Glumes similar; exceeding apex of florets; similar to fertile lemma in texture; gaping. Lower glume lanceolate; 18–22 mm long; 1 length of upper glume; membranous; without keels; 3 -veined. Lower glume surface asperulous. Lower glume apex acute. Upper glume lanceolate; 18–22 mm long; 2.5–2.8 length of adjacent fertile lemma; membranous; without keels; 3 -veined. Upper glume surface asperulous. Upper glume apex acute.

FLORETS Fertile florets female. Fertile lemma ovate; 7–8 mm long; membranous; without keel; 7 -veined. Lemma surface scaberulous; plumose; hairy below. Lemma hairs 5–6 mm long. Lemma apex lobed; 2 -fid; with filiform lobes; with lobes 0.3–1 mm long; acuminate; awned; 1 -awned. Principal lemma awn 4–8 mm long overall. Palea lanceolate; 5.5–6.3 mm long; 0.66 length of lemma; 2 -veined. Palea keels ciliolate. Palea surface glabrous, or pubescent; hairy on flanks. Palea apex dentate; 2 -fid. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3. Staminodes present; 1.5 mm long.

FRUIT Caryopsis with adherent pericarp.

MALE Male inflorescence bisexual similar to female; a panicle. Male spikelets resembling female.

DISTRIBUTION South America: western South America.

NOTES Arundineae. Conert 1993.

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