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.

Streptogyna

HABIT Perennial. Rhizomes absent (1), or elongated (1). Culms erect; 30–97.5–150 cm long. Ligule an eciliate membrane. Leaf-blade base with a false petiole. Leaf-blades lanceolate. Leaf-blade venation with distinct cross veins.

INFLORESCENCE Inflorescence composed of racemes.

Racemes single; unilateral. Rhachis semiterete. Spikelet packing broadside to rhachis; 1 -rowed.

Spikelets appressed; solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–4 fertile florets; with diminished florets at the apex. Spikelets linear, or oblong; laterally compressed; 20–25–30 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes definite. Floret callus elongated; glabrous (1), or pubescent (1).

GLUMES Glumes persistent; shorter than spikelet; thinner than fertile lemma. Lower glume lanceolate; 0.2–0.35–0.5 length of upper glume; scarious; 1-keeled; 3 -veined. Lower glume surface without pits. Lower glume apex acute. Upper glume lanceolate; 1 length of adjacent fertile lemma; scarious; 1-keeled; 9 -veined (1), or 17 -veined (1). Upper glume lateral veins with cross-veins. Upper glume apex acute; mucronate.

FLORETS Fertile lemma oblong; subterete; coriaceous; without keel; wingless; 9 -veined. Lemma surface unwrinkled; without grooves; glabrous (1), or pilose (1). Lemma margins convolute; covering most of palea. Lemma apex dentate; truncate; awned; 1 -awned. Principal lemma awn from a sinus. Palea keels contiguous above a sulcus. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 3; membranous; ciliate; obtuse. Anthers 2. Stigmas 2–3 (1); papillose (1), or retrorsely barbellate (1). Ovary glabrous (1), or pubescent on apex (1).

FRUIT Caryopsis with adherent pericarp; linear; isodiametric; biconvex; apex rostrate. Embryo 0.1 length of caryopsis. Hilum linear; 1 length of caryopsis.

DISTRIBUTION Africa (1), or Tropical Asia (1), or North America (1), or South America (1).

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