Schultz, G. P. (4327 Meridian Ave. N., Seattle, WA 98103). Vascular flora of the El Edén Ecological Reserve, Quintana Roo, Mexico. J. Torrey Bot. Soc. 132: 311–322. 2005.—The El Edén Ecological Reserve, Quintana Roo, Mexico, is a 1500 hectare privately owned reserve created in 1992 for research and conservation of the dry tropical forests in the northeastern Yucatán Peninsula. The reserve lies within a greater bioregion known as the Yalahau, which has been noted for its extensive wetlands, rare elsewhere in the Peninsula. The vegetation of the reserve represents all the major vegetation types of the greater bioregion and includes mature semideciduous dry tropical forest, various aged stands of successional forest, seasonally inundated forest and palm/cattail savanna as well as several permanent water bodies. The purpose of this study is to document the flora of the reserve. The vascular flora of the El Edén Reserve includes comprises 404 species, 306 genera and 99 families. Ferns (Division Pteridophyta) account for 8 species and 8 genera in 7 families. Cycads (Division Cycadophyta) account for one species in one family. Flowering plants (Division Magnoliophyta) account for 395 species in 297 genera and 91 families. Monocots (Class Liliopsida) account for 68 species in 51 genera and 18 families. Dicots (Class Magnoliopsida) account for 327 species in 246 genera and 73 families. Exotics only account for 3.5% of the flora, and plants with pantropical distribution (mostly weedy herbs) account for 6.3%. Yucatán Peninsula endemics account for 9.5% (39 species) of the total flora.