We describe a new genus of anomaline scarab, Anomalorhina (Coleoptera: Scarabaeidae: Rutelinae: Anomalini) from Costa Rica and Nicaragua. Anomala turrialbana Ohaus is transferred into this genus, and a new species, Anomalorhina osaensis, is described. Anomalorhina is characterized by the clypeal apex that is abruptly reflexed, the base of the frons that has prominent tubercles in males, the pronotum with a depressed fovea in males, and the pronotum with the apical bead posteriorly produced and V-shaped at the middle in females. We summarize the biological importance of the 16 genera of New World anomaline scarabs, including comments on agricultural pests, larvae, and natural history. We provide an overview and synopsis of each of the New World anomaline genera with comments on biology and characteristics for identification.