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.

Triraphis

HABIT Annual (2), or perennial (6). Rhizomes absent (5), or short (1), or elongated (2). Culms erect (4/6), or geniculately ascending (1/6), or decumbent (2/6); slender (2/2); 3–46.43–120 cm long; firm (7), or woody (1). Culm-internodes terete (1/1). Lateral branches lacking (4/5), or ample (1/5). Ligule a fringe of hairs. Leaf-blades filiform (1), or linear (7).

INFLORESCENCE Inflorescence a panicle; exserted, or embraced at base by subtending leaf (1).

Panicle open (4), or contracted (3), or spiciform (1), or glomerate (1).

Spikelets solitary, or in pairs (1). Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 4 fertile florets (3), or 5 fertile florets (6), or 6–8 fertile florets (7), or 9–10 fertile florets (5), or 11 fertile florets (4), or 12–15 fertile florets (3), or 16–19 fertile florets (2), or 20–24 fertile florets (1); with diminished florets at the apex. Spikelets lanceolate (1), or oblong (7); laterally compressed; 4–7.375–15 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes definite; glabrous (6), or pubescent (1), or pilose (1). Floret callus brief (4), or evident (3), or elongated (1); pubescent (7), or pilose (1); obtuse (7), or acute (1).

GLUMES Glumes persistent (7), or deciduous (1); shorter than spikelet. Lower glume lanceolate; 0.7–0.8125–1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface without pits. Lower glume apex entire (5), or dentate (3); 2 -fid (3/3); acute (5/6), or acuminate (1/6); muticous (2), or mucronate (6), or awned (1). Upper glume lanceolate; 0.75–1.012–1.3 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume apex dentate; 2 -fid; muticous (2), or mucronate (3), or awned (4); 1 -awned (4/4).

FLORETS Fertile lemma elliptic (7), or oblong (1); membranous; keeled; wingless; 3 -veined. Lemma midvein eciliate (7), or ciliate (1). Lemma surface unwrinkled; without grooves; glabrous (5), or pilose (3). Lemma margins eciliate (1), or ciliate (7). Lemma apex dentate; 2 -fid; incised 0.25 of lemma length; awned; 3 -awned. Principal lemma awn from a sinus. Lateral lemma awns longer than principal (1/6), or subequal to principal (1/6), or shorter than principal (4/6). Palea 0.75 length of lemma; hyaline (1), or membranous (7); 2 -veined. Palea keels smooth (1), or scaberulous (7). Palea apex dentate (1/1). Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; fleshy. Anthers 3.

FRUIT Caryopsis with adherent pericarp; linear (6/7), or ellipsoid (1/7); trigonous (6/6). Embryo 0.5 length of caryopsis. Hilum linear (1/1); 0.25–0.29–0.33 length of caryopsis.

DISTRIBUTION Africa (6), or Temperate Asia (1), or Australasia (1), or South America (1).

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