Angiosperm Diversity in the Semiarid Region of Ceará State, Brazil, with Emphasis on Caatinga Species

Abstract We examined the taxonomic diversity of native angiosperms in the semiarid region of Ceará State, Brazil, emphasizing species occurring in Steppic Savanna. The diversity of native angiosperms comprises 120 families, 604 genera, and 1,443 species. Fabaceae was the most taxonomically diverse family, while Croton (Euphorbiaceae) was the most species rich genus (33 sp.). Steppic Savanna species account for 58% of all angiosperms recorded in Ceará State, and 41% of all species listed for that phytophysiognomy in Brazil. An update of the species richness within the Steppic Savanna of Ceará State phytogeographical area is provided, also indicating distribution data for other phytophysiognomies in Ceará.