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.

Thamnocalamus

HABIT Perennial. Rhizomes short; pachymorph. Culms erect; 300–433.3–700 cm long; woody; without nodal roots (1/1). Culm-internodes terete. Culm-nodes swollen (1/1). Lateral branches dendroid. Branch complement one (1), or two (1), or three (1), or several; in a horizontal line (2/2); with subequal branches (1/1); thinner than stem (1/1). Culm-sheaths deciduous (2/2); without auricles. Culm-sheath blade triangular (2/2). Ligule an eciliate membrane (1), or a ciliolate membrane (2). Leaf-blade base with a brief petiole-like connection to sheath. Leaf-blades linear (2), or lanceolate (2); herbaceous (2), or chartaceous (1). Leaf-blade venation with distinct cross veins.

INFLORESCENCE Synflorescence bractiferous (2/2); fasciculate (2/2); with spathaceous subtending bracts (2/2); without axillary buds at base of spikelet (2/2).

Fertile spikelets sessile (1/2), or pedicelled (1/2).

FERTILE SPIKELETS Spikelets comprising 3–4 fertile florets (1/2), or 5 fertile florets (2/2), or 6 fertile florets (1/2); with diminished florets at the apex (2/2). Spikelets oblong (2/2); laterally compressed (2/2); 25–31.75–40 mm long; breaking up at maturity (2/2); disarticulating below each fertile floret (2/2). Rhachilla internodes definite (2/2).

GLUMES Glumes persistent (2/2); shorter than spikelet (2/2). Lower glume lanceolate (2/2); 0.9–0.95–1 length of upper glume; chartaceous (2/2); without keels (2/2); 5 -veined (1/2), or 9 -veined (1/2). Lower glume surface without pits (2/2). Lower glume apex acuminate (2/2). Upper glume lanceolate (2/2); 0.7–1.075–1.6 length of adjacent fertile lemma; chartaceous (2/2); without keels (2/2); 7 -veined (1/2), or 9 -veined (1/2). Upper glume apex acuminate (2/2).

FLORETS Fertile lemma lanceolate (2/2); chartaceous (2/2); without keel (2/2); wingless (2/2); 5–9 -veined (1/2), or 13–15 -veined (1/2). Lemma surface smooth (1/2), or asperulous (1/2); unwrinkled (2/2); without grooves (2/2). Lemma apex attenuate (2/2); muticous (1/2), or awned (1/2); 1 -awned (1/1). Palea 4 -veined (1/2), or 8 -veined (1/2). Palea keels smooth (1/2), or scabrous (1/2); eciliate (1/2), or ciliolate (1/2). Apical sterile florets resembling fertile though underdeveloped (2/2).

FLOWER Lodicules 3 (2/2); glabrous (1/2), or ciliate (1/2). Anthers 3 (1/1). Stigmas 3 (2/2).

FRUIT Caryopsis with adherent pericarp (2/2); linear (1/1), or oblong (1/1).

DISTRIBUTION Temperate Asia (2), or Tropical Asia (2).

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