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.

Hemarthria

HABIT Annual (1), or perennial (11). Stolons absent (5), or present (7). Culms erect (1/10), or geniculately ascending (1/10), or prostrate (8/10); 16.72–95.13–250 cm long; rooting from lower nodes (7/7). Culm-internodes elliptical in section (1/1). Lateral branches sparse (1/11), or ample (10/11). Ligule a ciliolate membrane (1), or a ciliate membrane (11). Leaf-blades linear, or lanceolate (1).

INFLORESCENCE Inflorescence composed of racemes; subtended by an unspecialized leaf-sheath (3), or an inflated leaf-sheath (9); exserted (11), or embraced at base by subtending leaf (1).

Racemes single. Rhachis fracturing into irregular segments; flattened. Rhachis internodes columnar (8), or oblong (2), or cuneate (2); unspecialized (3), or adherent to upper glume of sessile spikelet (9). Rhachis internode tip transverse (3), or oblique (9); flat.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels fused to internode; oblong; tip rectangular.

STERILE SPIKELETS Companion sterile spikelets rudimentary (1), or well-developed (11); deciduous with the fertile. Companion sterile spikelet glumes muticous (2/3), or awned (3/3).

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets linear (2), or lanceolate (4), or elliptic (4), or oblong (6); dorsally compressed; 3–7.295–24 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus square (1), or cuneate (11); glabrous (11), or pubescent (1); base truncate; attached transversely (1), or attached obliquely (11).

GLUMES Glumes exceeding apex of florets; firmer than fertile lemma. Lower glume linear (2), or lanceolate (4), or elliptic (4), or oblong (6); herbaceous (11), or coriaceous (1); 2-keeled; wingless (1), or winged on keel (11); 7 -veined (2/3), or 9–15 -veined (1/3). Lower glume intercarinal veins distinct (11/11). Lower glume surface convex (2), or flat (10); not waisted, or transversely waisted (2); without pits. Lower glume apex entire (11), or dentate (1); 2 -fid (1/1); emarginate (3), or truncate (1), or obtuse (5), or acute (4), or acuminate (4), or attenuate (2), or setaceously attenuate (1), or rostrate (1), or caudate (2); muticous, or awned (1). Upper glume linear (2), or elliptic (2), or oblong (8); membranous (11), or coriaceous (1); without keels; 3 -veined, or 4–5 -veined (1). Upper glume apex obtuse (1/11), or acute (7/11), or acuminate (4/11), or attenuate (4/11), or setaceously attenuate (2/11), or cuspidate (1/11), or caudate (1/11); muticous, or awned (1); 1 -awned (1/1).

FLORETS Basal sterile florets male (4), or barren (9); with palea (5), or without significant palea (7). Lemma of lower sterile floret oblong; hyaline; 2 -veined (2/2); obtuse (11/11). Fertile lemma oblong; hyaline; without keel; wingless; 0 -veined. Lemma surface unwrinkled; without grooves. Lemma apex obtuse (11/11). Palea present (2), or absent or minute (10); hyaline (2/2); 0 -veined (2/2); without keels (2/2).

FLOWER Anthers 3 (10/10).

FRUIT Caryopsis with adherent pericarp; obovoid (2/2); dorsally compressed (2/2).

DISTRIBUTION Europe (1), or Africa (2), or Temperate Asia (5), or Tropical Asia (10), or Australasia (1), 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.