Ceiba guarani (Malvaceae, Bombacoideae), a new species from sub-Andean southern Bolivia and the Sierras of northwestern Argentina

Based on observations made during botanical surveys in the southern sub-Andean of Bolivia, analysis of collected material, review of herbarium material and online databases, we determined that the Ceiba populations of the xeric Bolivian-Tucuman forests, previously identified as Ceiba chodatii, correspond to a new species. Given that the morphological, ecological and distributional characteristics differ from those observed in populations of C. chodatii, we propose Ceiba guarani sp. nov. Our field observations and distribution data from the revised specimens indicate that C. chodatii is naturally restricted to the Chaco plains and a strip of the southern Subandean foothills, whereas Ceiba guarani is distributed mainly in the Subandean ranges.