Rhytachne guianensis

HABIT Perennial. Culms erect; 100 cm long. Ligule a ciliolate membrane; 0.5 mm long. Leaf-blades convolute; 15–25 cm long; 3–4 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; smoothly terete; 10–20 cm long. Rhachis fragile at the nodes; semiterete; glabrous on surface; glabrous on margins. Rhachis internodes columnar; 5–8 mm long. Rhachis internode tip transverse; crateriform; with simple rim.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; foliaceous; curved; glabrous.

STERILE SPIKELETS Companion sterile spikelets rudimentary; comprising 2 subequal glumes without lemmas; 0.5–1 mm long; deciduous with the fertile. Companion sterile spikelet glumes chartaceous; muticous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 5–8 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus glabrous; base truncate; with central peg; attached transversely.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume oblong; 1 length of spikelet; coriaceous; without keels. Lower glume surface smooth. Lower glume apex acute; muticous. Upper glume oblong; membranous; 3 -veined. Upper glume muticous.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret lanceolate; hyaline; acute. Palea of lower sterile floret 0.66 length of lemma. Fertile lemma lanceolate; hyaline; without keel. Lemma apex acute. Palea 0.5 length of lemma.

FLOWER Anthers 3.

DISTRIBUTION South America: northern South America, western South America, and Brazil.

NOTES Andropogoneae. WDC.

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