A key to species and descriptions are presented for 14 species of the New World genus Crassomicrodus Ashmead. Seven new species, Crassomicrodus azteca, Crassomicrodus clypealis, Crassomicrodus costaricensis, Crassomicrodus jalisciensis, Crassomicrodus mariae, Crassomicrodus oaxaquensis,and Crassomicrodus olgae are described. Crassomicrodus fenestratus (Viereck) is synonymized with Crassomicrodus nigriceps (Cresson). Crassomicrodus melanopleurus (Ashmead) is recognized as a valid species.
Keywords: Ichneumonoidea; insecta; new species; parasitoid wasps; taxonomy.