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.

Tetrapogon ferrugineus

HABIT Perennial; caespitose. Rhizomes short. Basal innovations flabellate. Culms geniculately ascending, or decumbent; 15–104 cm long; 2–4 -noded. Leaf-sheaths keeled. Ligule a ciliolate membrane. Leaf-blades filiform; involute; 25–35 cm long; 3–4 mm wide. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 8; digitate; unilateral; 4–11 cm long. Spikelet packing broadside to rhachis.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with diminished florets at the apex. Spikelets cuneate; laterally compressed; 2–2.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pilose; obtuse.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma; gaping. Lower glume lanceolate; 4–4.5 mm long; 0.8 length of upper glume; membranous; pallid; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acuminate; muticous, or mucronate. Upper glume lanceolate; 4–5.5 mm long; 2 length of adjacent fertile lemma; membranous; pallid; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex acuminate; muticous, or mucronate.

FLORETS Fertile lemma elliptic; laterally compressed; elliptic in profile; 2.5 mm long; coriaceous; dark brown; keeled; 3 -veined. Lemma lateral veins close to margins. Lemma surface pubescent; with conspicuous apical hairs. Lemma hairs red. Lemma apex obtuse; awned; 1 -awned. Principal lemma awn subapical; 3.5–4 mm long overall. Apical sterile florets 2 in number; barren; separate; elliptic. Apical sterile lemmas pubescent; awned; 1 -awned. Apical sterile lemma awns subapical; 2 per spikelet in number.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3. Stigmas 2.

FRUIT Caryopsis with adherent pericarp; trigonous. Hilum punctiform.

DISTRIBUTION Africa: northeast tropical and east tropical.

NOTES Cynodonteae. FW 1995.

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