A New Deciduous Species of Pachira (Malvaceae: Bombacoideae) from a Seasonally Dry Tropical Forest in Northeastern Brazil

Pachira (Malvaceae: Bombacoideae) is distributed predominantly in northern South America and is the largest genus in the subfamily, including about 50 species. Ongoing studies of the systematics of neotropical Bombacoideae and field work in northeastern Brazil led to the discovery of a new species, herein described and illustrated. Pachira moreirae is known from a single population that is endemic to caatinga vegetation (a type of seasonally dry tropical forest) in the state of Bahia. The new species is leafless during its flowering period, a condition commonly seen in some genera of Bombacoideae but rare in Pachira, a genus that mostly comprises evergreen species. We provide a description of the morphology of this new species and notes on its distribution, phenology, and conservation status. A phylogenetic analysis using ITS data shows that P. moreirae is a member of a Brazilian extra-Amazonian clade of Pachira that also includes P. glabra and P. refuse.