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

HABIT Perennial. Rhizomes absent (11), or short (2). Culms erect (11), or geniculately ascending (5); robust (1/1); 15–44.3–100 cm long. Culm-internodes similar in length (6/7), or unequal, the upper longer (1/7). Lateral branches lacking (7/8), or sparse (1/8). Ligule a ciliolate membrane (3), or a ciliate membrane (1), or a fringe of hairs (9). Leaf-blades linear, or lanceolate (2); stiff (1), or firm (12).

INFLORESCENCE Inflorescence a panicle (1), or composed of racemes (12); exserted, or embraced at base by subtending leaf (1).

Panicle open (1/1).

Racemes single (1/12), or borne along a central axis (12/12); erect (4/12), or ascending (9/12), or spreading (1/12); unilateral (12/12); bearing few fertile spikelets (5/12), or many spikelets (7/12); bearing 1–2 fertile spikelets on each (1/2), or 6–8 fertile spikelets on each (1/2). Spikelet packing lax (12/12).

Spikelets solitary. Fertile spikelets pedicelled. Pedicels oblong (9/9).

FERTILE SPIKELETS Spikelets comprising 2 fertile florets (4), or 3 fertile florets (11), or 4 fertile florets (12), or 5 fertile florets (9), or 6 fertile florets (4), or 7 fertile florets (3), or 8 fertile florets (1); with diminished florets at the apex. Spikelets lanceolate; laterally compressed; 5–8.596–13 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes definite; glabrous (4), or pubescent (9). Floret callus pubescent (10/10).

GLUMES Glumes persistent; shorter than spikelet; parallel to lemmas (10), or gaping (3). Lower glume linear (1), or lanceolate (12), or oblong (1), or ovate (1); 0.4–0.6673–0.9 length of upper glume; hyaline (1), or membranous (12); 1-keeled; 0 -veined (1), or 1 -veined (11), or 2 -veined (1), or 3 -veined (3), or 4–5 -veined (1). Lower glume lateral veins absent (10), or distinct (4). Lower glume surface smooth (7), or scabrous (6); without pits. Lower glume apex truncate (1/12), or obtuse (4/12), or acute (10/12); muticous, or mucronate (1). Upper glume linear (1), or lanceolate (10), or oblong (2), or ovate (2); 0.33–0.7077–0.9 length of adjacent fertile lemma; hyaline (1), or membranous (12); 1-keeled; 0 -veined (1), or 1 -veined (10), or 2 -veined (3), or 3 -veined (6), or 4–5 -veined (3), or 6–7 -veined (1). Upper glume surface smooth (7), or scabrous (6). Upper glume apex obtuse (3), or acute (12), or acuminate (1); muticous, or mucronate (1).

FLORETS Fertile lemma lanceolate (11), or ovate (2); membranous; keeled; wingless; 3 -veined (5), or 4 -veined (4), or 5 -veined (12), or 6–7 -veined (1). Lemma midvein without distinctive roughness (12), or scaberulous (1). Lemma lateral veins obscure (1/1). Lemma surface smooth (6), or asperulous (7); unwrinkled; without grooves; glabrous (11), or pubescent (1), or pilose (1). Lemma margins eciliate (3), or ciliolate (2), or ciliate (3), or pubescent (5). Lemma apex entire (5), or dentate (8); 2 -fid (8/8); truncate (1/2), or obtuse (2/2), or acute (1/2); muticous (1), or mucronate (5), or awned (10); 1 -awned (10/10). Principal lemma awn apical (5), or from a sinus (8). Palea 1 length of lemma; 2 -veined (12/12). Palea keels smooth (7), or scaberulous (1), or scabrous (5); eciliate (10), or ciliolate (3). Palea surface glabrous (10), or pubescent (1), or pilose (2). Palea apex entire (1/8), or dentate (8/8); muticous (9), or with excurrent keel veins (1), or awned (3). Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; fleshy. Anthers 3.

FRUIT Caryopsis with adherent pericarp (12/12); lanceolate (1/1).

CLEISTOGENES AND VIVIPARY Cleistogenes present; in upper sheaths.

DISTRIBUTION Europe (2), or Temperate Asia, or Tropical Asia (1).

Please cite this publication as detailed in How to Cite Version: 16th November 2012.