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.

Tenaxia

HABIT Perennial. Rhizomes absent (6), or short (2). Culms erect (3/3), or geniculately ascending (1/3); 10–46.71–117 cm long. Lateral branches lacking (2/2). Ligule a fringe of hairs. Leaf-blades aciculate (1), or filiform (6), or linear (2); herbaceous (6), or coriaceous (2); stiff (4), or firm (4). Leaf-blade margins cartilaginous (1/1). Leaf-blade apex muticous (7), or pungent (1).

INFLORESCENCE Inflorescence a panicle (7), or composed of racemes (2), or comprising only a few spikelets (1).

Panicle open (3/7), or contracted (5/7).

Racemes single (2/2); unilateral (1/2), or paucilateral (1/2). Rhachis angular (1/1).

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets (3), or 3–5 fertile florets (6), or 6–7 fertile florets (3); with diminished florets at the apex. Spikelets cuneate; laterally compressed; 9–15–25 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes definite. Floret callus evident; pubescent (1), or pilose (5), or bearded (2).

GLUMES Glumes persistent; shorter than spikelet (1), or exceeding apex of florets (7); thinner than fertile lemma; gaping. Lower glume lanceolate, or elliptic (1); 0.8–0.975–1 length of upper glume; membranous; without keels; 1–2 -veined (1), or 3 -veined, or 4–5 -veined (6), or 6–7 -veined (1). Lower glume surface without pits. Lower glume apex acute (3), or acuminate (6), or attenuate (1); muticous (7), or mucronate (1). Upper glume lanceolate (7), or elliptic (2); 1–1.812–2.5 length of adjacent fertile lemma; membranous; with undifferentiated margins (6), or hyaline margins (2); without keels; 1–2 -veined (1), or 3 -veined (5), or 4 -veined (4), or 5 -veined (7), or 6–7 -veined (2). Upper glume apex acute (3), or acuminate (6), or attenuate (1); muticous (7), or mucronate (1).

FLORETS Fertile lemma elliptic (2), or oblong (6); chartaceous (7), or coriaceous (1); without keel; wingless; 5–7 -veined (1), or 9 -veined (7). Lemma surface unwrinkled; without grooves; glabrous (6), or pubescent (2), or pilose (1); without hair tufts (1), or with basal hair tufts near margin (2), or with marginal hair tufts (3), or with a transverse row of hair tufts (2). Lemma margins eciliate (5), or ciliate (3). Lemma apex lobed; 2 -fid; incised 0.25–0.4494–0.7 of lemma length; acute (1/1), or acuminate (1/1); awned; 1 -awned (2), or 3 -awned (6). Principal lemma awn from a sinus; geniculate. Lateral lemma awns shorter than principal (2/2). Palea 1 length of lemma; 2 -veined (2/2). Palea keels smooth (4), or scaberulous (2), or scabrous (2); eciliate (4), or pubescent (3), or ciliolate (1). Palea surface glabrous (5), or puberulous (2), or pilose (1). Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous (2), or fleshy (6); ciliate. Anthers 3.

FRUIT Caryopsis with adherent pericarp; oblong (1/3), or obovoid (2/3). Embryo 0.5 length of caryopsis. Hilum elliptic (1/1).

DISTRIBUTION Africa (6), or Temperate Asia (3), or Tropical Asia (2).

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