The Cicadellidae comprise a large assemblage of poorly defined subfamilies with uncertain relationships. In attempting to place a new leafhopper genus(Tinteromus) from Costa Rica, in an existing subfamily, we used a phenetic analysis involving several similar groups. Table 2 shows the similarity values between these groups and the new taxa. Results suggest that the new genus is not closely related to any known subfamily and a new subfamily Tinterominae, is proposed. Descriptions are given for the above new taxa and for two new species:T. omaniandT. nigricornis.