Floristic Inventory of the Iguaçu and Iguazú National Parks (Brazil and Argentina): Bignoniaceae

Abstract

Although Argentina and Brazil are among the countries with the highest vascular plant diversity, the flora of both countries remains understudied. The Iguazú region, where the Iguaçu National Park (Brazil) and the Iguazú National Park (Argentina) are located, is an example of a region that remains poorly known botanically. Even though the Bignoniaceae is an important component of the flora of this region, few floristic treatments are available for this plant family for the Southern Cone, a region encompassing Chile, Argentina, Uruguay, Paraguay, and Southern Brazil. Here, we provide a floristic account of Bignoniaceae from the Iguazú and Iguaçu National Parks, including identification keys, photographs, illustrations, comments on the geographic distribution, habitat, and phenology. A total of 29 species in 13 genera of Bignoniaceae were documented. Of these, Dolichandra and Fridericia are the richest genera in the region, with five species each, followed by Adenocalymma, Handroanthus, and Jacaranda with three species each, and Amphilophium and Bignonia with two species each. Six genera, i.e., Mansoa, Podranea, Pyrostegia, Tabebuia, Tanaecium, and Tynanthus, are represented by a single species. As scientific novelties herein we document Fridericia triplinervia for the first time in the PARNA Iguaçu, a new collection of Dolichandra cynanchoides in the PARNA Iguaçu after 54 years, Tynanthus micranthus distribution expansion to Argentina, the correction of the endemism status of Jacaranda micrantha and Jacaranda puberula, as well as the preliminar assessment of most of the species conservation status. This way, our findings expand the knowledge about the flora of the Southern Cone, contributing with important information for the establishment of biodiversity management plans and conservation priorities.