|Abstract||Three new species re described: two belonging to the genus Incidifrons Ewing 1929: I. dissimilis (ex. Fulica gigantea Eydoux & Souleyet) and I. leucopterae (ex. Fulica leucoptera Vieillot) and oe to Rallicola Johnston & Harrison 1916: R. cornutae (Ex. Fulica cornuta Bonapartae). The diagnosis of R. taylori Emerson, 1955, R. andinus Carriker, 1949, and R. minutus (Nitzsch in Giebel, 1866) are amplified with new data. Geographical distributions of R. wernecki Emerson, 1955, R. guimaraesi, Emerson, and R. leucopterae Cicchino, 1980 are enlarged with new records. Affinities are briefly discussed for some of the treated species, and a key for all described species of Incidifrons and Rallicola known as parasitic coots (genus Fulica Linnaeus, 1758) is provided.