Tarenaya longicarpa, commonly known as “mussambê,” is a new species from South America. Iltis previously recognized it as a subspecies of Cleome spinosa Jacq. but never published the name. Molecular phylogenetic studies have confirmed this taxon as a distinct lineage from T. spinosa. In addition, the results of a revision of Tarenaya, now underway, corroborate the separation of T. longicarpa from T. spinosa s. s.