Taxonomia de Neptunia Lour. (Caesalpinioideae) nas Américas e educação ambiental com as leguminosas na Caatinga

Abstract

Neptunia Lour. (Leguminosae-Caesalpinioideae) has a pantropical distribution, with about 12 species. It is characterized by the heteromorphic flowers and yellow petaloid staminodes, often associated with flooded environments. Revisional studies for Neptunia date back over 50 years, demonstrating the need for taxonomic and nomenclatural updates, since the taxa present cryptic and polymorphic characters, leading to imprecisions in identifications, and consequently, cascading failure. The objectives of this thesis were: (1) to perform a taxonomic revision and morphological characterization of Neptunia in the Americas and (2) to develop an environmental education program, focused on the Leguminosae family, for the visitors and seed collectors in Floresta Nacional de Açu. For the 1st objective, collections were made following the usual methodology, as well as analysis in national and international herbaria. For the Americas, five species were revised, with comments, identification key, distribution data and illustrations. To clarify the nomenclatural history of the genus, we assigned lectotypes to six names: Neptunia depauperata, N. tenuis, N. pubescens, N. mazatlana, N. pubescens var. microcarpa and N. palmeri. and synonymization of N. amplexicaulis f. richmondii and N. gracilis f. glandulosa under N. amplexicaulis and N. gracilis, respectively. The proposal for environmental education aimed at valuing the flora of the caatinga, through the identification of trees, mainly legumes, 92 individuals were marked and identified in the field, of which 13 species and 34 individuals of Leguminosae, and 58 individuals and 21 species belong to the families Anacardiaceae, Apocynaceae, Bignoniaceae, Bixaceae, Boraginaceae, Burseraceae, Cactaceae, Capparaceae, Combretaceae, Chrysobalanaceae, Euphorbiaceae, Malvaceae and Rhamnaceae. Posteriorly, educational signs about legumes and other species were developed and three options of trails were mapped, serving both basic school students, researchers, and seed collectors. It is concluded that the present work has advanced the knowledge about legumes and Neptunia, contributing to an increase in collections and a deepening of the knowledge of the taxonomy of the genus. Also, we could implement, in practice, strategies to combat plant awareness disparity and to popularize science, promoting the caatinga’s flora.