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.

Poa andina

HABIT Perennial. Rhizomes elongated. Butt sheaths herbaceous; persistent and investing base of culm; with fibrous dead sheaths. Culms 20–70 cm long. Culm-internodes terete; smooth. Lateral branches lacking. Leaf-sheaths smooth; glabrous on surface. Ligule a ciliolate membrane; 2–3 mm long; pubescent on abaxial surface; truncate. Leaf-blades flat, or conduplicate; 2–18(–30) cm long; 6–12 mm wide. Leaf-blade surface glabrous. Leaf-blade apex pungent.

INFLORESCENCE Gynodioecious ("male", in this context, indicating the bisexual state). Inflorescence a panicle. Peduncle smooth.

Panicle open; elliptic; 15 cm long. Primary panicle branches 3–4 -nate; 4–9 cm long. Panicle branches smooth.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–4 fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; 6–7.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes scaberulous. Floret callus pilose. Floret callus hairs 0.33–0.5 length of lemma.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 0.9 length of upper glume; membranous; 1-keeled; 1–3 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent, or obscure. Lower glume apex acute. Upper glume lanceolate; 6–7 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scabrous. Upper glume apex acute.

FLORETS Fertile florets female. Fertile lemma lanceolate; oblong in profile; 6.5–7 mm long; membranous; keeled; 5 -veined. Lemma surface scabrous; pubescent; hairy on veins. Lemma apex emarginate; awned; 1 -awned. Principal lemma awn from a sinus; 0.5–1 mm long overall. Palea 0.9 length of lemma. Palea keels scabrous; adorned above. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 3–3.5 mm long; purple. Staminodes present; 1.5–3 mm long.

FRUIT Caryopsis with adherent pericarp; ellipsoid; 2 mm long. Hilum punctiform.

MALE Male inflorescence bisexual similar to female.

DISTRIBUTION South America: southern South America.

NOTES Poeae. Fl Pat.

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