The Pantepui in the Brazilian Amazon: Vascular Flora of Serra Do Aracá, a Cradle of Diversity, Richness and Endemism

Formed by tall flat-topped mountains known as tepuis, the Pantepui is an important center of vascular plant endemism and diversity in South America. In Brazil, the Pantepui is mostly on the border of Venezuela, and an isolated area, Serra do Araca, stands out as the tepui southernmost. In this paper we present a floristic survey of the vascular plants that occur on Serra do Araca, compare the richness to other tepuis, and commented on the conservation of Amazonian “campos rupestres”. Our dataset includes over 1600 records, either collected by us in three field expeditions, or by other botanists. A checklist with 436 species of vascular plants is provided. Our study also shows that among the 34 tepuis of the Pantepui, Serra do Araca ranks tenth in species richness and has 24 endemic species. Serra do Araca, like other tepuis, houses representatives of ancestral lineages of vascular plants of South America, showing how important tepuis are as cradles of lineages. Despite its importance for Amazonian biodiversity, Serra do Araca is one of the natural reserves in the Amazon with the highest number of requests for mining.