The cacao bud mite, Aceria reyesi (Nuzzaci 1973) (Eriophyidae), reported as causing serious damage to the cacao tree in Central and South America, is studied based on type specimens from Venezuela and adults and immatures specimens from Costa Rica, Ecuador and the Brazilian states of Amazonas, Bahia and Rondônia, offering a supplementary description and the first report of this species in Costa Rica and Ecuador. The probable origin and the potential geographic distribution of this noxious phytophagous mite is discussed, and a detailed morphological comparison between A. reyesi and the related eriophyid species Gymnaceria cupuassu Oliveira, Rodrigues & Flechtmann 2012, both associated with Theobroma species (Malvaceae) of economic importance, is given.