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.

Dignathia

HABIT Annual (3), or perennial (2). Culms erect (3), or geniculately ascending (2), or decumbent (2); slender (1/1); 5–25.2–60 cm long; firm (1), or wiry (2), or woody (2). Lateral branches lacking (1/3), or sparse (1/3), or ample (1/3), or suffrutescent (1/3). Ligule a ciliate membrane. Leaf-blades persistent (3), or deciduous at the ligule (2); stiff (2), or firm (3).

INFLORESCENCE Inflorescence composed of racemes; subtended by an unspecialized leaf-sheath (4), or an inflated leaf-sheath (1); exserted (4), or embraced at base by subtending leaf (2).

Racemes borne along a central axis; in a multilateral false spike; ascending (3), or spreading (2); linear (1), or oblong (4); unilateral; bearing few fertile spikelets; bearing 1 fertile spikelets on each (4), or 2 fertile spikelets on each (3), or 3 fertile spikelets on each (1). Rhachis deciduous from axis; flattened; terminating in a spikelet (1), or sterile spikelet (4). Raceme-bases brief (3), or cuneate (2).

Spikelets solitary (3), or in pairs (4), or in threes (1). Fertile spikelets sessile; 1–2 in the cluster (2/2); subequal (2/2).

FERTILE SPIKELETS Spikelets comprising 1 fertile florets (4), or 3 fertile florets (1); without rhachilla extension. Spikelets lanceolate (1), or ovate (2), or orbicular (2); laterally compressed; symmetrical (2), or gibbous (3); 2–5–7 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes exceeding apex of florets (4/4); firmer than fertile lemma; parallel to lemmas (2), or recurved at apex (2), or gaping (1). Lower glume subulate (1), or lanceolate (4); gibbous; 0.7–0.9375–1 length of upper glume; cartilaginous (1), or coriaceous (4); 1-keeled (4/4); 1 -veined (4/4). Lower glume lateral veins absent (4), or distinct (1). Lower glume surface smooth (3), or scabrous (2); without pits; glabrous (2), or puberulous (1), or pubescent (1), or villous (1). Lower glume apex acute (2/4), or acuminate (1/4), or caudate (1/4); muticous (3/4), or awned (1/4). Upper glume lanceolate (2/4), or orbicular (2/4); gibbous; 1–1.187–1.7 length of adjacent fertile lemma; cartilaginous (1), or indurate (4); with undifferentiated margins (1), or hyaline margins (4); 1-keeled (4/4). Upper glume primary vein eciliate (3), or ciliolate (1), or ciliate (1). Upper glume surface smooth (3), or scabrous (2); glabrous (2), or puberulous (1), or pubescent (1), or villous (1); with simple hairs (2/3), or tubercle-based hairs (1/3). Upper glume apex acuminate (1/4), or caudate (3/4); muticous (3/4), or awned (1/4); 1 -awned (1/1).

FLORETS Fertile lemma elliptic (1), or ovate; not gibbous (3), or gibbous (2); membranous (3), or cartilaginous (2); keeled; wingless; 3 -veined (4/4). Lemma midvein eciliate (1), or ciliolate (1), or ciliate (2), or pubescent (1). Lemma surface unwrinkled; without grooves; glabrous (4), or puberulous (1), or pubescent (1). Lemma apex acute (3), or acuminate (2); mucronate (3), or awned (2); 1 -awned (2/2). Palea 2 -veined (4/4).

FLOWER Anthers 3.

FRUIT Caryopsis with adherent pericarp; ellipsoid (3/3); dorsally compressed (3/3); plano-convex (3/3).

DISTRIBUTION Africa, or Temperate Asia (1), or Tropical Asia (1).

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