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.

Hymenachne

HABIT Perennial. Rhizomes absent (5), or elongated (2). Culms erect (1/6), or decumbent (5/6); robust (3/3); 20–176.6–400 cm long; spongy (1), or firm (6); rooting from lower nodes (5/5). Culm-internodes terete (1/1). Lateral branches lacking (2/4), or ample (2/4). Ligule an eciliate membrane. Leaf-blades linear (2), or lanceolate (6); stiff (1), or firm (6). Leaf-blade midrib conspicuous (2/2). Leaf-blade margins unthickened (1/1).

INFLORESCENCE Inflorescence a panicle.

Panicle open (3), or contracted (2), or spiciform (2).

Spikelets appressed (1/1); solitary (5), or in pairs (2), or in threes (1). Fertile spikelets pedicelled. Pedicels filiform (1/5), or linear (2/5), or oblong (2/5).

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate (5), or elliptic (2); dorsally compressed; 1.7–3.17–5.5 mm long; falling entire.

GLUMES Glumes shorter than spikelet (3), or reaching apex of florets (4); thinner than fertile lemma. Lower glume ovate; clasping (3/3); hyaline (5), or membranous (2); without keels; 1 -veined (1), or 3 -veined (5), or 5–7 -veined (1). Lower glume lateral veins absent (1), or distinct (6); without ribs (5/6), or ribbed (1/6). Lower glume surface smooth, or asperulous (1); without pits. Lower glume apex obtuse (1), or acute (5), or cuspidate (1). Upper glume lanceolate (4), or elliptic (3); membranous; without keels; 3 -veined (2/6), or 4 -veined (1/6), or 5 -veined (4/6), or 7 -veined (1/6). Upper glume lateral veins without ribs (6), or ribbed (1). Upper glume apex acute (5), or acuminate (1), or caudate (1); muticous (3), or awned (4); 1 -awned (4/4).

FLORETS Basal sterile florets male (1), or barren (6); with palea (1), or without significant palea (6). Lemma of lower sterile floret lanceolate (4), or elliptic (1), or oblong (2); membranous (6), or chartaceous (1); 3 -veined (2), or 4 -veined (1), or 5 -veined (6); without ribs (6), or ribbed (1); obtuse (1), or acute (3), or acuminate (1), or caudate (2). Fertile lemma lanceolate (1), or elliptic (3), or ovate (3); dorsally compressed (2/2); chartaceous (2), or cartilaginous (5); of similar consistency on margins (6), or much thinner on margins (1); without keel; wingless; 3 -veined (4/5), or 5 -veined (1/5). Lemma surface unwrinkled; without grooves. Lemma margins involute. Lemma apex acute (4), or acuminate (3); without ornament (5), or scabrous (2). Palea embraced by lemma (3), or separating from lemma above (4); not rolled (1), or involute (6); 0.8–0.95–1 length of lemma; chartaceous (2), or cartilaginous (5); 2 -veined (4/4); without keels (4), or 2-keeled (3).

FLOWER Anthers 3 (6/6).

FRUIT Caryopsis with adherent pericarp (1/1); ellipsoid (2/4), or oblong (1/4), or obovoid (1/4). Embryo 0.5 length of caryopsis. Hilum elliptic (1/1).

DISTRIBUTION Africa (2), or Temperate Asia (3), or Tropical Asia (2), or Australasia (1), or North America (1), or South America (4).

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