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.

Dactyloctenium

HABIT Annual (8), or perennial (5). Stolons absent (7), or present (7). Culms erect (3/11), or geniculately ascending (6/11), or decumbent (8/11), or prostrate (1/11); 3–34.76–160 cm long; without nodal roots (1/8), or rooting from lower nodes (8/8). Lateral branches ample (1/2), or suffrutescent (1/2). Ligule an eciliate membrane (3), or a ciliolate membrane (10), or a ciliate membrane (1). Leaf-blades herbaceous (11), or coriaceous (2); stiff (2), or firm (11). Leaf-blade apex muticous (11), or pungent (2).

INFLORESCENCE Inflorescence composed of racemes.

Racemes single (1), or paired (2), or digitate (12); not compacted (5/12), or in a head (7/12); erect (1), or ascending (12), or spreading (3); linear (7), or oblong (8); unilateral. Rhachis deciduous from axis; flattened; terminating in a barren extension; extension subulate (3), or bristle-like (10). Spikelet packing broadside to rhachis; crowded; 2 -rowed.

Spikelets pectinate (12/12); solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets (1), or 2 fertile florets (4), or 3–4 fertile florets (11), or 5 fertile florets (8), or 6 fertile florets (4), or 7 fertile florets (2), or 8–9 fertile florets (1); with diminished florets at the apex. Spikelets lanceolate (1), or elliptic (2), or oblong (1), or ovate (11); laterally compressed; 2.3–4.447–8 mm long; breaking up at maturity; disarticulating above glumes but not between florets. Spikelet callus glabrous (1/2), or pubescent (1/2), or pilose (1/2). Rhachilla internodes definite (12/12).

GLUMES Glumes persistent; shorter than spikelet (12), or reaching apex of florets (1), or exceeding apex of florets (1); parallel to lemmas (11), or recurved at apex (2). Lower glume lanceolate (2), or elliptic (3), or oblong (4), or ovate (6); 0.7–0.9962–1.3 length of upper glume; membranous (5/5); 1-keeled; wingless (10), or winged on keel (4); 1 -veined. Lower glume lateral veins absent (12), or distinct (1). Lower glume surface without pits. Lower glume apex truncate (1), or acute (12); muticous (12), or mucronate (1). Upper glume elliptic (3), or oblong (7), or ovate (3), or obovate (1); 0.4–0.6423–1 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume apex truncate (6), or obtuse (2), or acute (5); mucronate (1), or awned; 1 -awned. Upper glume awn terminal (5), or subapical (8).

FLORETS Fertile lemma ovate (3/3); not gibbous (9), or gibbous (4); lanceolate in profile (6/10), or elliptic in profile (1/10), or ovate in profile (5/10); membranous; keeled; wingless; 1 -veined (1), or 3 -veined (12). Lemma midvein without distinctive roughness (3), or scaberulous (8), or scabrous (2). Lemma lateral veins obscure (8/8). Lemma surface unwrinkled; without grooves. Lemma apex acute (9), or acuminate (2), or setaceously attenuate (1), or cuspidate (3); muticous (5), or mucronate (9), or awned (2); 1 -awned (2/2). Palea 1 length of lemma; 2 -veined (12/12). Palea keels wingless (10), or winged (5); smooth (9), or scaberulous (4); eciliate (11), or ciliolate (2). Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3.

FRUIT Caryopsis with free soft pericarp (12/12); ellipsoid (2/9), or oblong (1/9), or orbicular (1/9), or obovoid (7/9); laterally compressed (1/1); granular (5/9), or rugose (4/9).

DISTRIBUTION Europe (1), or Africa (12), or Temperate Asia (4), or Tropical Asia (3), or Australasia (5), or Pacific (1), or North America (1), or South America (1).

Please cite this publication as detailed in How to Cite Version: 27th January 2014.