Twenty-one species of Tarsonemus known from New York are keyed. Five new species are described and illustrated: Tarsonemus acerbilis and T. edwardi found associated with eriophyid mites in galls, and T. blakemorei, T. socius and T. vulgaris taken from bird nests and stored grain. Five tarsonemid mites previously reported from nest habitat are newly recorded from stored grain; these are: T. ascitus Delfinado, T. confusus Ewing, T. granarius Lindquist, T. imitatus Delfinado and T. waitei Banks.