The North American genus Slaterocoris Wagner is revised and now contains 32 species. The new genus Josephinus is erected to accommodate three Mexican species, the type species, Slaterocoris reinhardi Carvalho and Schaffner, 1973, along with Scalponotatus albicornis Kelton, 1970, and Scalponotatus capitatus Kelton, 1970. Slaterocoris argenteoides, S. clavatus, S. elongatus, S. maculatus, and S. tanydexios from southern Mexico are described as new. The new combinations Slaterocoris punctatus (Distant, 1893) [Jornandes] and Slaterocoris subalbicans (Distant, 1893) [Jornandes] are proposed resulting in two subjective junior synonyms of Slaterocoris for the monotypic genera, Guerrerocoris Carvalho and China, 1959 and Amulacoris Carvalho and China, 1959, respectively. A review of the genus Scalponotatus Kelton, 1969, provides a new diagnosis and description of the genus and the type species, S. maturus Kelton, 1969, and a checklist of the nine species included in the newly conceived genus. Based on examination of the holotypes, the new combinations, Scalponotatus dissimulans (Distant, 1893) [Jornandes] and Jornandes sinaloensis (Carvalho and Costa, 1992) [Scalponotatus] are proposed. The following 23 new specific subjective synonymies are proposed (senior synonym first): Slaterocoris alpinus Kelton, 1968  =  Slaterocoris schaffneri Knight, 1970; Slaterocoris ambrosiae (Knight, 1938) [Strongylocoris]  =  Slaterocoris arizonensis Knight, 1970, Slaterocoris bispinosus Knight, 1970, Slaterocoris ovatus Knight, 1970, and Slaterocoris severini Knight, 1970; Slaterocoris apache Kelton, 1968  =  Slaterocoris bifidus Knight, 1970 and