The monotypic genus Teskeyellus was described for T. hirsuticornis Philip & Fairchild 1974, from Mexico. After more than 40 years, another species is described in the genus, T. cyanommatus sp. nov., based on two females and one male specimens from Amazon basin. The type specimens of T. hirsuticornis were studied and we concluded that there are enough similarities to include the new species in Teskeyellus.
Keywords: Horse flies; neotropics; new taxon; taxonomy.