A new genus Ami Pérez-Miles is proposed for six new species: A. caxiuana Pérez-Miles, Miglio & Bonaldo, from Caxiuanã National Forest, Pará, Brasil, the type species; A. yupanquii Pérez-Miles, Gabriel & Gallon, from the area of Puyo, Equador; A. bladesi Pérez-Miles, Gabriel & Gallon, from Isla Colón, Panamá; A. pijaos Jimenez & Bertani, from Ibagué, Tolima, Colombia; A. amazonica Jimenez & Bertani, from Leticia, Amazonas, Colombia; and A. weinmanni Pérez-Miles, from La Azulita, Apure, Venezuela. Avicularia obscura (Ausserer 1875) is transferred to Ami and re-diagnosed. Diagnostic characters of Ami are the modification of Type I urticating hairs, with unusually longer area b, and one or two subconical processes on retrolateral face of male palpal tibiae. Females of Ami differ further from those of other theraphosid genera by their highly characteristic spermathecae: paired ventral receptacles attached to an almost discrete, semicircular, sclerotized back-plate.