Advances in knowledge of Manihot (Euphorbiaceae) from Brazil.

Herbarium-based studies and extensive field work revealed the existence of a new species in the genus Manihot which is restricted to the municipality of Itirapina, in the state of São Paulo, Brazil. Characteristics such as the size and morphology of the leaves and bracts were important to recognize M. irregularis as a new taxon. Description, illustration, as well as comments on its morphology, distribution, conservation status, and a key for the identification of Manihot species for the state of São Paulo are presented.