Two new species of rust fungi (Pucciniales) from the Brazilian Amazon: Aecidium margaritariae on Margaritaria and Uromyces amapaensis on Jatropha

ABSTRACT Two new species of Pucciniales fungi on plants of the Fabid clade are described from samples deposited in the herbarium of Museu Paraense Emilio Goeldi, collected in the state of Amapá, in the Brazilian Amazon. They are Aecidium margaritariae found on Margaritaria nobilis (Phyllanthaceae), and Uromyces amapaensis on Jatropha gossypiifolia (Euphorbiaceae). The microstructures of the specimens were analyzed using optical and scanning electron microscopy. Aecidium margaritariae is characterized by the presence of globose, subglobose to slightly ellipsoid aeciospores with warty walls and smooth areas usually in the basal portion. Uromyces amapaensis is distinguished by the presence of uredinia with paraphyses which are thickened and rounded at the tip, and pedicellate and smooth teliospores. Descriptions, illustrations, and taxonomic comments are presented for each species.