Problematic specimens turn out to be two undescribed species of Bignonia (Bignoniaceae)

Bignonia comprises 29 species of lianas characterized by eight phloem wedges, leaves usually 2-foliolate, mostly simple tendrils and opaque seed wings. The analysis of herbarium specimens in preparation for a taxonomic revision of the genus led to the recognition of two new species: (i) Bignonia cararensis from Costa Rica, characterized by a thyrse with lateral compound dichasia and lack of interpetiolar ridge, and (ii) Bignonia sanctae-crucis from Bolivia and Brazil, distinguishable by its membranous leaflets, membranous calyx and small fruits. We provide detailed descriptions, illustrations, distribution maps, initial conservation status assessments, and comparisons of the newly described taxa with closely related species.