Valner Jordao1P, Fabiana Filardi1, Domingos Cardoso1

1Research Institute of the Rio de Janeiro Botanical Garden, Rio de Janeiro, Brazil

The taxonomic study of the Brazilian flora began in the XIX century with extensive collections made by European and Brazilian botanists, culminating in the publication of Flora brasiliensis (FB). This monumental work documented over 22,000 plant species and established the first comprehensive taxonomic framework for Brazil’s extraordinarily rich flora, including the early treatment of the species-rich genus Machaerium, for which 43 species were recognized. More than a century later, the launch of Flora e Funga do Brasil (FFB) online marked a new phase in documenting Brazilian biodiversity. Supported by digitized herbarium collections, integrated national biodiversity databases, and broad taxonomic collaboration, the FFB provides up-to-date, openly accessible monographs for all Brazilian plant, algal, and fungal species, now recognizing 53,699 species. Widely distributed across Brazil and exhibiting pronounced morphological and ecological diversity, Machaerium is represented by 74 species in FFB, out of an estimated 130 total, reflecting a substantial increase of approximately 72% compared to FB. We expect this number to grow, as our recent taxonomic studies have identified 11 new species for Brazil — five from the Caatinga, one from the Cerrado, and five from the Amazon — which are currently under morphological and molecular study. Advancing and maintaining a complete, up-to-date monograph of Machaerium is essential not only to refine the taxonomy of the genus, but also to highlight the importance of detailed monographic studies in achieving a comprehensive Flora of Brazil, while also supports conservation assessments by enabling the identification of threatened species and priority areas for biodiversity protection.