Tropical forests are the terrestrial ecosystems with the greatest spatial heterogeneity and local diversity of species, as well as a complex horizontal and vertical structure that makes them unique. Their importance as an ecosystem lies in the great variety of habitats that they This is due to their biotic and genetic potential, their high degree of endemicity and biodiversity, which makes it essential to know and protect them. This work takes us into the forests of Calderas, Barinas state in Venezuela, which show changes in structure and floristic composition along an altitudinal gradient that ranges between 921-1710 masl and contribute three new records to the Venezuelan vascular flora Andira macrothyrsa Ducke of the leguminous plants (Fabaceae, Papilionoideae), Guatteria verrucosa R.E.Fr. (Annonaceae) and Heisteria aff. silvianii of the family Erythropalaceae.The text should summarize the contents of the book, which should appear on the cover and in various catalogs of bookstores.