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.

Pleuropogon

HABIT Annual (1), or perennial (4). Rhizomes absent (1), or elongated (4). Culms erect (3/3), or geniculately ascending (1/3); 5–74.5–150 cm long; spongy (1), or firm (4). Ligule an eciliate membrane.

INFLORESCENCE Inflorescence composed of racemes.

Racemes single; bilateral; bearing few fertile spikelets; bearing 5–10 fertile spikelets on each (2/2), or 11–12 fertile spikelets on each (1/2). Spikelet packing broadside to rhachis; distant.

Spikelets appressed (2/4), or ascending (2/4), or deflexed (2/4); solitary. Fertile spikelets pedicelled. Pedicels linear.

FERTILE SPIKELETS Spikelets comprising 5 fertile florets (1), or 6 fertile florets (2), or 7 fertile florets (3), or 8 fertile florets, or 9–12 fertile florets (4), or 13 fertile florets (1); with diminished florets at the apex. Spikelets linear, or oblong (3); laterally compressed; 10–23.77–40 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes definite.

GLUMES Glumes persistent; shorter than spikelet; thinner than fertile lemma. Lower glume oblong (4), or ovate (1); 0.5–0.76–1 length of upper glume; hyaline; without keels; 0 -veined (1), or 1 -veined (4). Lower glume lateral veins absent. Lower glume surface without pits. Lower glume apex erose; obtuse (1), or acute (4). Upper glume oblong (4), or ovate (1); 0.25–0.635–0.8 length of adjacent fertile lemma; hyaline; without keels; 0–1 -veined (1), or 3 -veined (3). Upper glume apex erose; obtuse (1), or acute (4).

FLORETS Fertile lemma oblong (1), or ovate (4); chartaceous; without keel; wingless; 7 -veined. Lemma lateral veins without ribs (4), or ribbed (1). Lemma surface smooth (2), or asperulous (2), or scabrous (1); unwrinkled; without grooves. Lemma apex erose (4), or dentate (1); 2 -fid (1/1); emarginate (1/4), or obtuse (3/4), or acute (2/4); awned; 1 -awned. Principal lemma awn apical (4), or from a sinus (1). Palea 1 length of lemma; 2 -veined. Palea keels winged; with toothed wings (3), or each wing 1-awned (1), or each wing 2-awned (1); smooth (3), or scaberulous (2). Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; united; fleshy; truncate. Anthers 3 (4/4).

FRUIT Caryopsis with adherent pericarp; ellipsoid (1/1); dorsally compressed (1/1). Embryo 0.4 length of caryopsis. Hilum linear; 1 length of caryopsis.

DISTRIBUTION Europe (1), or Temperate Asia (1), or North America.

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