The family Cheyletiellidae is divided into five subfamilies based on differences in habitat, host preferences, and on morphological features. These are: Ornithocheyletiinae, n. subfam., Teinocheyletinae, n. subfam., Criokerontiane, n. subfam., and Niheliiane, n. subfam., and Cheyletiellinae. A key is provided for subfamilial separation and differentation. New species of Ornithocheyletia Volgin and Neocheyletiella Baker are described and illustrated. New keys to the species of these genera are included. Heteromorphic males are now known to occur in the Ornithocheyletiinae. The males and nymph are described and illustrated for Ornithocheyletia hallae Smiley. Developmental stages of this species (eggs nand larvae) have been found in the epidermal tissues of a pigeon with thick scales caused by hyphae of an actinomycete, suggesting that the species may be partially endoparasitic.