Author Institution: Department of Zoology, The Ohio State University, Columbus, Ohio 43210Two new genera, Alladanus and Cozadanus, and sixteen new species of Deltocephalinae (leafhoppers) are described from Mexico. Twelve species, all new, are described and placed in the genus Eutettix Van Duzee: E. contorqus, E. lanceolatus, E. dentatus, E. alvadus, E. chelatus, E. spinus, E. pedus, E. divergens, E. krameri, E. guevarai, E. transversus, and E. ortegai. Two new species, A, cephalatus and A. mexellus, are described and placed in the new genus Alladanus, of which A. cephalatus is the genotype. Two new species, C. globosus and C. serratus, are described and placed in the new genus Cozadanus, of which C. globosus is the genotype
