Abstract
Begonia microinduta, a new species of Begonia sect. Pritzelia from the Atlantic Coastal Forest of Brazil is described and illustrated with detailed field photographs. This species is similar to B. windischii and B. lorenzii by having three tepals on pistillate flowers, staminate flowers with pilose dorsal surface, short peduncled inflorescences, very short inflorescence ramification and persistent floral bracts. It differs from B. windischii in its petiole indumentum, which is covered with short microscopic trichomes throughout (vs. sparsely pilose in the upper third with villous trichomes, with a trichome necklace at the base of the petiole and in the apex) and differs from B. lorenzii by having microscopic (vs. villous) trichomes, glabrous (vs. pubescent) adaxial leaf surface and glabrous (vs. pubescent) fruits.