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Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Puccinellia acroxantha

HABIT Perennial; caespitose; clumped loosely. Basal innovations extravaginal and intravaginal. Culms erect, or geniculately ascending; 30–60 cm long; 2 -noded. Culm-internodes terete; smooth; distally glabrous. Lateral branches lacking. Leaf-sheaths loose; striately veined; smooth; glabrous on surface. Ligule an eciliate membrane; 2–3.5 mm long; obtuse. Leaf-blades convolute; 9–18 cm long; 1–2 mm wide. Leaf-blade surface scaberulous; rough adaxially; glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; linear; 12–20 cm long; 1.5 cm wide. Primary panicle branches appressed; simple; 1–5 cm long. Panicle axis with lower internodes 2–4.5 cm long; scaberulous; with scattered hairs. Panicle branches flexuous; scaberulous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 1–2.5 mm long.

FERTILE SPIKELETS Spikelets comprising 3–5 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 5 mm long; 1.5 mm wide; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume ovate; 1–1.3 mm long; 0.5–0.66 length of upper glume; membranous; much thinner above; much thinner on margins; without keels; 1–3 -veined. Lower glume lateral veins absent, or obscure. Lower glume apex obtuse. Upper glume ovate; 2 mm long; 0.75 length of adjacent fertile lemma; membranous; much thinner above; with hyaline margins; without keels; 3 -veined. Upper glume apex obtuse.

FLORETS Fertile lemma oblong; 2.5–2.8 mm long; membranous; much thinner above; much thinner on margins; mid-green and yellow; tipped with last colour; without keel; 5 -veined. Lemma midvein pubescent; hairy below. Lemma lateral veins stopping well short of apex. Lemma margins pubescent; hairy below. Lemma apex obtuse. Palea 1 length of lemma; 2 -veined. Palea keels ciliate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Africa: south.

NOTES Poeae. CEH 1999.

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