Conservation, spatial distribution, and endemism of Pilosocereus cacti in xeric environments of the Neotropics

Abstract

Urgent strategies for the conservation of the Neotropical flora are needed in the face of accelerated habitat loss and a severe biodiversity crisis. To assess the conservation status and to propose protection programs for taxa under potential risk, such as the Cactaceae, a group strongly affected by disturbances and habitat loss, detailed data describing patterns of richness, diversity, and endemism is paramount. Among cacti, Pilosocereus is considered a good model to study biodiversity patterns because of its remarkable occurrence in Neotropical xeric environments. Here we analyzed species occurrence under climate, soil, and biomes data using a similarity analysis and a parsimony analysis of endemicity to provide an overview on the patterns of distribution, richness, and endemism of Pilosocereus. To further evaluate whether current protected areas ensure the conservation of the group’s taxonomic and phylogenetic diversity we performed a gap analysis. We found the greatest species richness and phylogenetic diversity in eastern Brazil and areas of endemism are highlighted in eastern Brazil as well as in Mexico. As these areas shelter great diversity and uniqueness, we recommend they become a focus for the conservation of the group and possibly for other Neotropical drought-adapted taxa.