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.

Gouinia mexicana

HABIT Perennial. Culms erect; 150–200 cm long. Lateral branches lacking. Leaf-sheaths longer than adjacent culm internode; smooth, or scaberulous. Ligule an eciliate membrane, or a ciliolate membrane; 1 mm long; erose. Leaf-blades 20–35 cm long; 15–22 mm wide. Leaf-blade surface smooth, or scaberulous. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 20–25; borne along a central axis; spreading; unilateral; 5–26 cm long. Central inflorescence axis 30–40 cm long. Rhachis angular. Spikelet packing lax. Raceme-bases filiform; 10–80 mm long.

Spikelets appressed; solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 3–4 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 15 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet; similar to fertile lemma in texture. Lower glume lanceolate; 5 mm long; 0.7–0.8 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scaberulous. Lower glume apex acute. Upper glume ovate; 6 mm long; 0.75 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein scaberulous. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 8–9 mm long; membranous; keeled; 3 -veined. Lemma midvein ciliate. Lemma margins ciliate. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn 2–3 mm long overall. Palea 0.75 length of lemma. Palea keels ciliate. Apical sterile florets 1 in number; barren; lanceolate. Apical sterile lemmas awned.

FLOWER Anthers 3.

DISTRIBUTION North America: Mexico.

NOTES Eragrostideae. Swallen.

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