The Neotropical genus Cryptocanthon Balthasar (Scarabaeinae: Canthonini) is revised. Diagnoses, descriptions and a key to the 35 species are presented, including 22 new species:C. bochilae, C. howdeni, C. montebello, C. ocosingo and C. rayonensis from Mexico; C. osaensis and C. solisi from Costa Rica; C. denticulum and C. lobipygus from Panama; C. escobari, C. foveatus, C. medinae and C. pumilus from Colombia; C. andersoni, C. gilli and C. punctatus from Venezuela; C. galbao from French Guiana; C. curticrinus, C. genieri, C. napoensis, C. otonga and C. urguensis from Ecuador. All of the known species of Cryptocanthon are inhabitants of wet forest litter. A phylogenetic hypothesis and biogeographical discussion are included. Based on the phylogenetic analysis, four species groups were established: a northern South America relict species group, an Amazonian-Guianan lowland species group, a middle American species group, and a northern Andean species group. The diversity and level of endemicity of Cryptocanthon is consistent with other small-sized scarab beetles.