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.

Stenostachys

HABIT Perennial. Stolons absent (3), or present (1). Culms erect (1), or geniculately ascending (2), or decumbent (2); robust (1/3), or weak (2/3); 25–61.25–100 cm long. Leaf-sheath auricles absent (3), or falcate (1). Ligule an eciliate membrane. Leaf-blades firm (2), or flaccid (2).

INFLORESCENCE Inflorescence composed of racemes.

Racemes single; ascending (3), or drooping (1); bilateral; bearing 10–14 fertile spikelets on each (1), or 15–18 fertile spikelets on each (2), or 19 fertile spikelets on each (1), or 20–30 fertile spikelets on each (3), or 31–40 fertile spikelets on each (1). Rhachis flattened. Spikelet packing broadside to rhachis; contiguous (3), or lax (1). Rhachis internodes linear (1), or oblong (3). Rhachis internode tip flat (1/1).

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1–2 fertile florets (3), or 3 fertile florets (2), or 4 fertile florets (1); with a barren rhachilla extension (3), or with diminished florets at the apex (3). Spikelets lanceolate (3), or elliptic (1), or oblong (1); laterally compressed (1), or dorsally compressed (3); 7–11.25–16 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes definite (3/3); glabrous (1/3), or pubescent (2/3). Floret callus brief (3), or evident (1); pubescent (2/3), or bearded (1/3).

GLUMES Glumes both absent or obscure (1), or two (3); persistent (3/3); shorter than spikelet (3/3). Lower glume subulate (2/3), or lanceolate (1/3); 1 length of upper glume; coriaceous (1/1); without keels (1/1); 3–5 -veined (1/1). Lower glume surface without pits (3/3). Lower glume apex setaceously attenuate (1/1). Upper glume subulate (2/3), or lanceolate (1/3); 0.25–0.6875–1 length of adjacent fertile lemma; coriaceous (1/1); without keels (1/1); 3–5 -veined (1/1). Upper glume apex setaceously attenuate (1/1).

FLORETS Fertile lemma lanceolate (2), or elliptic (2); coriaceous; without keel (3/3); wingless; 3–4 -veined (2/3), or 5 -veined (3/3). Lemma surface smooth (1), or asperulous (1), or scaberulous (3), or scabrous (1); unwrinkled; without grooves. Lemma apex entire (2), or dentate (3); 2 -fid (2/3), or 3 -fid (1/3); acute (1/2), or attenuate (1/2); mucronate (1), or awned (3); 1 -awned (3/3). Principal lemma awn apical (3), or from a sinus (2). Palea 0.9–0.9667–1 length of lemma; 2 -veined (2/2). Palea keels smooth (3), or scabrous (1); eciliate (3), or ciliolate (2). Apical sterile florets resembling fertile though underdeveloped (1/3), or distinct from fertile (2/3).

FLOWER Lodicules 2 (2/2); membranous (1/1). Anthers 3. Stigmas 2 (1/1). Ovary pubescent on apex (2/2).

FRUIT Caryopsis with adherent pericarp. Embryo 0.2–0.225–0.25 length of caryopsis.

DISTRIBUTION Australasia.

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