The genus Mecynippus Bates, 1884 is investigated and considered a monotypic genus. Falsomecynippus Bi, Chen & Lin, gen. nov., is established for Monohammus ciliatus Gahan, 1888 which was previously placed in Mecynippus. One new subgenus is described based on Falsomecynippus (Tuberculhammus) superbus Bi, Chen & Lin, subgen. nov. & sp. nov. from China and Laos. Illustrations of the habitus, endophallic structures, and major diagnostic features for all involved taxa are provided.