DIVERSITY AND DISTRIBUTION OF SOLANUM SUBG. LEPTOSTEMONUM IN BRAZIL

Solanum subg. Leptostemonum (Solanaceae) is the second largest subgenus of Solanum, with approximately 450 species. It is of cosmopolitan distribution with its primary center of diversity in South America and secondary centers in Australia and Africa. Morphological characters used to distinguish it from other subgenera include a stellate indument, prickly herbage and attenuate anthers. In Brazil, approximately 455 specific names have been applied to the species of subgenus Leptostemonum, of which 345 are synonyms. Solanum subg. Leptostemonum is represented in Brazil by about 110 species, including undescribed taxa; of these, 58 are endemic (about 53%). They are assigned to the following sections: Acanthophora, Crinitum, Melongena, Erythrotrichum, Herposolanum, Lasiocarpa, Micracantha, Persicariae, Polytrichum and Torva. They are encountered in many kinds of vegetation and display marked adaptations to humid or dry, hot and seasonal habitats. The principal center of diversity and endemism in Brazil is found in the southeastern coastal region, which has about 64 species (representing 58% of the total Brazilian species) and 20 endemics.