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.

Cleistogenes serotina

HABIT Perennial; culms solitary. Basal innovations extravaginal. Culms geniculately ascending; 30–60(–90) cm long; 1 mm diam.; 10–16 -noded. Culm-internodes similar in length. Culm-nodes brown; glabrous. Leaf-sheaths tight; longer than adjacent culm internode; smooth, or scaberulous. Ligule a fringe of hairs; 0.4 mm long. Leaf-blades spreading; flat, or involute; 4–8 cm long; 3–5 mm wide. Leaf-blade surface scaberulous; rough on both sides. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes borne along a central axis; spreading; unilateral; 1–4 cm long; bearing 6–8 fertile spikelets on each. Central inflorescence axis 4–8 cm long. Spikelet packing lax.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels oblong; 1–4 mm long.

FERTILE SPIKELETS Spikelets comprising 3–5 fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; 8–11 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1.2–1.5 mm long; pubescent; hairy at tip. Floret callus pubescent.

GLUMES Glumes persistent; dissimilar; shorter than spikelet. Lower glume lanceolate; 2.3–2.8 mm long; 0.75 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume surface scabrous. Lower glume apex acute. Upper glume lanceolate; 3–4 mm long; 0.66 length of adjacent fertile lemma; membranous; 1-keeled; 1–3 -veined. Upper glume lateral veins absent, or distinct. Upper glume surface scabrous. Upper glume apex acute, or acuminate.

FLORETS Fertile lemma lanceolate; 5–6 mm long; membranous; mid-green and purple; keeled; 5 -veined. Lemma surface asperulous. Lemma margins ciliolate; hairy below. Lemma hairs 0.5 mm long. Lemma apex dentate; 2 -fid; with lobes 0.1 mm long; mucronate, or awned; 1 -awned. Principal lemma awn from a sinus; 0.5–1 mm long overall. Palea 1 length of lemma; 2 -veined. Palea keels scabrous. Palea surface pubescent; hairy on flanks. Palea apex dentate; 2 -fid; with excurrent keel veins. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 2.5 mm long.

FRUIT Caryopsis with adherent pericarp.

CLEISTOGENES AND VIVIPARY Cleistogenes present; in upper sheaths.

DISTRIBUTION Europe: central, southwestern, southeastern, and eastern. Asia-temperate: Soviet Middle Asia, Caucasus, and western Asia.

NOTES Eragrostideae. Conert.

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