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.

Periballia

HABIT Annual. Culms erect (1/1), or decumbent (1/1); 3–20.5–40 cm long. Ligule an eciliate membrane.

INFLORESCENCE Inflorescence a panicle.

Panicle open. Primary panicle branches without sterile bristles (2), or sterile at lowest node (1).

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform; tip pyriform.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; without rhachilla extension. Spikelets elliptic; laterally compressed; 1.5–2.176–3 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes definite; glabrous (2), or pubescent (1). Floret callus pubescent (1/2), or pilose (1/2).

GLUMES Glumes persistent; shorter than spikelet, or reaching apex of florets (1); thinner than fertile lemma (2), or similar to fertile lemma in texture (1). Lower glume lanceolate (2), or elliptic (1); 0.9–0.9667–1 length of upper glume; hyaline (2), or membranous (1); 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface without pits. Lower glume apex obtuse (1), or acute. Upper glume lanceolate (1), or elliptic (1), or ovate (1); 0.8–0.9167–1.1 length of adjacent fertile lemma; hyaline (2), or membranous (1); 1-keeled; 1 -veined (2), or 3 -veined (1). Upper glume apex obtuse (1), or acute.

FLORETS Fertile lemma oblong (2), or ovate (1); membranous; without keel; wingless; 3 -veined (1), or 5 -veined (2), or 6–7 -veined (1). Lemma midvein without distinctive roughness (2), or scaberulous (1). Lemma surface smooth (2), or asperulous (1); unwrinkled; without grooves; glabrous (2), or pubescent (1). Lemma apex obtuse (2), or acute (1); muticous (2), or awned (2); 1 -awned (2/2). Principal lemma awn dorsal (2/2). Palea 1 length of lemma.

FLOWER Anthers 3.

DISTRIBUTION Europe, or Africa (2), or Temperate Asia (1), or Australasia (1).

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