What is Femuros (Cynipidae: Cynipini)?

The North American oak gall wasp genus Femuros Kinsey is revised after its re-establishment in 2015. Morphological evidence suggests that only 3 species described by Kinsey belong to this genus: F. repandae Kinsey, F. ocri Kinsey, and F. ruidum Kinsey. The rest of the species are transferred to the genus Andricus Hartig: A. geniale (Kinsey) comb. rev., A. integrum (Kinsey) comb. rev., A. lusum (Kinsey) comb. rev., and A. perfectum (Kinsey) comb. rev. A new species with slightly swollen femora but without an apical lobe and without internal tibial carina is described: A. calvoi sp. nov. We provide descriptions, redescriptions, diagnoses, keys to species, and information on biology, phenology, and distribution.