Urotocus rossittensis occurs in the bursa Fabricii of the scarlet-rumped tanager, Ramphocelus passerinii, and the common bush tanager, Chlorospingus ophthalmicus, from the Area de Conservación Guanacaste, Costa Rica. Morphological examination of type material of U. fusiformis and U. kenyensis and Costa Rican specimens suggests that U. fusiformis and U. kenyensis are indistinguishable from U. rossittensis. Confirmed accounts of Urotocus spp. refer to a single adult morphotype whose geographic distribution includes the Palearctic, Africa, Nearctic, and northern Neotropics.