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.

Glyceria

HABIT Annual (1), or perennial (45). Rhizomes absent (31), or short (2), or elongated (15). Stolons absent (44), or present (2). Culms erect (18/37), or geniculately ascending (14/37), or decumbent (15/37), or prostrate (3/37); robust (1/2), or weak (1/2); 10–76.9–250 cm long; spongy (2), or firm (44); without nodal roots (2/12), or rooting from lower nodes (12/12). Lateral branches lacking (2/2). Leaf-sheaths tubular for much of their length (33/33). Ligule an eciliate membrane. Leaf-blades membranous (1), or herbaceous (45); stiff (2), or firm (43), or flaccid (1). Leaf-blade midrib conspicuous (1/1). Leaf-blade venation without cross veins (44), or with obscure cross veins (1), or with distinct cross veins (1). Leaf-blade margins cartilaginous (1/1).

INFLORESCENCE Inflorescence a panicle; exserted (44), or embraced at base by subtending leaf (4).

Panicle open (39), or contracted (7).

Spikelets appressed (4/7), or ascending (4/7); solitary. Fertile spikelets sessile (1), or pedicelled (45). Pedicels filiform (1/1).

FERTILE SPIKELETS Spikelets comprising 2–7–20 fertile florets; with diminished florets at the apex. Spikelets linear (10), or lanceolate (8), or elliptic (5), or oblong (29), or ovate (10); laterally compressed (42), or subterete (5); 3–12.56–40 mm long; persistent on plant (1), or breaking up at maturity (45); disarticulating below each fertile floret (45/45). Rhachilla internodes definite; glabrous (45), or pubescent (1). Floret callus glabrous (4/4).

GLUMES Glumes persistent (45/45); shorter than spikelet; thinner than fertile lemma (1), or similar to fertile lemma in texture (45). Lower glume lanceolate (21), or elliptic (3), or oblong (16), or ovate (12); 0.33–0.6816–0.9 length of upper glume; hyaline (2), or membranous (44); without keels; 1 -veined (42/43), or 3–5 -veined (1/43). Lower glume lateral veins absent (42), or distinct (4). Lower glume surface without pits; glabrous (45), or puberulous (1). Lower glume apex entire (43), or erose (4); obtuse (24/42), or acute (21/42). Upper glume lanceolate (19), or elliptic (3), or oblong (19), or ovate (12); 0.25–0.7402–1.3 length of adjacent fertile lemma; hyaline (2), or membranous (44); with undifferentiated margins (34), or hyaline margins (11), or scarious margins (1); without keels; 1 -veined (41/43), or 2 -veined (1/43), or 3 -veined (2/43), or 5 -veined (1/43). Upper glume surface glabrous (45), or puberulous (1). Upper glume apex entire (43), or erose (4); obtuse (26/42), or acute (20/42).

FLORETS Fertile lemma lanceolate (6), or elliptic (6), or oblong (24), or ovate (15), or obovate (2), or flabellate (1); membranous (45), or coriaceous (1); of similar consistency above (19), or much thinner above (27); of similar consistency on margins (39), or much thinner on margins (7); without keel (45), or keeled (1); wingless; 5–6 -veined (1/40), or 7 -veined (39/40), or 11 -veined (1/40). Lemma lateral veins obscure (3/19), or with distinct primaries but obscure intermediates (2/19), or distinct (2/19), or prominent (12/19); extending close to apex (1/1). Lemma surface smooth (20), or asperulous (4), or scaberulous (18), or scabrous (5), or tuberculate (1); unwrinkled; without grooves; glabrous (45), or puberulous (1). Lemma apex entire (34), or erose (9), or dentate (4); 2 -fid (1/4), or 3 -fid (3/4), or 4–5 -fid (1/4); truncate (1/42), or obtuse (30/42), or acute (11/42), or acuminate (2/42), or attenuate (1/42). Palea 0.9–1.011–1.2 length of lemma; 2 -veined. Palea keels unthickened (45), or thickened (1); wingless (33), or winged (13); smooth (36), or scaberulous (7), or scabrous (3); eciliate (43), or ciliolate (3). Palea surface glabrous (45), or puberulous (1). Palea apex entire (1/14), or erose (1/14), or dentate (13/14). Apical sterile florets resembling fertile though underdeveloped (45), or distinct from fertile (1); 1 in number (1/1); barren (1/1); cuneate (1/1).

FLOWER Lodicules 2 (39/39); united (39/39); fleshy (39/39); truncate (39/39). Anthers 2 (5/39), or 3 (35/39).

FRUIT Caryopsis with adherent pericarp (43/43); ellipsoid (7/12), or oblong (5/12), or ovoid (1/12); laterally compressed (2/3), or dorsally compressed (1/3); rugose (1/1). Embryo 0.2 length of caryopsis. Hilum linear (36/36); 1 length of caryopsis.

DISTRIBUTION Europe (11), or Africa (3), or Temperate Asia (23), or Tropical Asia (4), or Australasia (9), or Pacific (1), or North America (18), or South America (6), or Antarctica (1).

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