Diversity of Bignoniaceae in coastal Piauí, Northeast Brazil

Abstract The present study is a taxonomic treatment of Bignoniaceae from the four municipalities of the coastal region of Piauí state (Cajueiro da Praia, Ilha Grande, Luís Correia, Parnaíba) in Northeast Brazil, based on morphological study of newly collected and existing herbarium material. The study recorded 26 species in 12 genera: Adenocalymma, Anemopaegma, Bignonia, Cuspidaria, Dolichandra, Fridericia, Handroanthus, Lundia, Neojobertia, Pleonotoma, Stizophyllum and Tanaecium. Apart from Handroanthus impetiginosus, which belongs to tribe Tecomeae, all other species belong to tribe Bignonieae. Five species (Adenocalymma apparicianum, A. pedunculatum, Anemopaegma heringeri, A. prostratum, Dolichandra hispida) are new records for the state of Piauí, 15 species are endemic to Brazil, and one has “Vulnerable” conservation status. The results emphasize the importance of taxonomic studies for knowledge of biodiversity and threats to native species, and reinforce the importance of conserving the region’s flora. Species descriptions, illustrations, identification keys and information on geographic distribution and habitat are provided.