Monographs Details:
Authority:

Mori, S. A., et al. 1997. Guide to the vascular plants of central French Guiana: Part 1. Pteridophytes, gymnosperms, and monocotyledons. Mem. New York Bot. Gard. 76: 1-422.
Family:

Cyperaceae
Description:

Species Description - Robust, caespitose perennials; culms erect, 45-150 cm tall, 3-sided. Leaves basal or cauline; largest leaves with sheath ca. 6-15 cm long, green or tinged reddish; blade 1-1.5 m x 9-28 mm, green adaxially and abaxially or occasionally tinged reddish at base abaxially, the margins usually slightly scabrous. Inflorescences 3-7 branched panicales; bract subtending each panicale leaf- like, the basal bract with a sheath 1.4 -4(7)cm long and a blade 65-100 x 0.9-28cm; each panicle with a peduncle 3-7(10)cm long, each branch terminating in 1-3 fruit - bearing spikelets or a secondary panicle. Fruiting spikelets ca. 2- 2.8 mm diam., the longest scales 3-4 x(1.6) 2.6 -3.2mm, the tip acuminate. Fruits plano-convex, the convex side depressed-obloid, 1.7-2.8 x 0.6-1.2 mm, white to tan or rarely brown, smooth to slightly rugulose, shiny; hypogynium subtending fruit as wide as fruit. Fr (year round); well-drained forests, usually on slopes. Koyama (1967) recognized two subspecies: B. cymosa subsp. cymosa and B. cymosa subsp. merkehana (Nees) T. Koyama. The former is characterized by fruits at least 2.5 mm wide, by spikelet scales (glumes) 3-3.5 mm long and by looser and less branched inflorescences, while the latter is characterized by fruits <2mm wide, by scales 2.5-3mm long, and by denser, more highly branched inflorescences. Material from French Guiana shows continuous variation in these features making disticntion of two subspecies impossible in our flora.