Flora de leguminosae Juss., do Parque Nacional Serra da Capivara, Piauí, Brasil

Abstract

The family Leguminosae Juss. is the third largest family of angiosperms in the world, comprising over 22,000 species and nearly 800 genera, with a cosmopolitan distribution occurring on almost every continent, except Antarctica. It holds great importance in terms of food, economy, ornamentation, and ecology. The Serra da Capivara National Park is one of the most important conservation units in both the state of Piauí and Brazil, due to its significant contribution to the understanding of the first peoples who inhabited the Americas. It also plays a vital role in the field of biology, hosting a rich fauna and flora, predominantly within the Caatinga phytogeographic domain, and remains relatively understudied in terms of floristic surveys. The aim of this study was to provide a species list of Leguminosae for Serra da Capivara National Park through botanical collections conducted between 2023 and 2024. These collections took place along random trails within the park and its permanent preservation areas (APPs), and included analysis of virtual herbarium specimens that were properly georeferenced within the park’s boundaries. For the identification of botanical material, comparisons were made with herbarium specimens, specialized literature was used, and experts contributed to the analysis, thereby enhancing the botanical knowledge of the area and of the state of Piauí. A total of 43 genera and 76 species of legumes were recorded, corresponding to approximately 11.6% of the species reported for the Caatinga biome and 19% of those cited for Piauí. The Caesalpinioideae subfamily showed the greatest species richness (35 spp.) across 14 genera. The Papilionoideae subfamily included 27 species and had the highest number of genera (23). The most species-rich genera were Mimosa L. and Bauhinia L., each with six species. Among the recorded species, 44 are endemic to Brazil, 21 are exclusive to the Caatinga, and seven are new records for the flora of Piauí. The data presented expand the understanding of Leguminosae diversity in Serra da Capivara National Park and in Piauí, and highlight the importance of conserving the most underprotected phytogeographic domain in the country.