Protolithocolletis lathyri is a moth of the family Gracillariidae. It is known from California and Michigan in the United States and from British Columbia east to Manitoba in Canada. The larvae feed on Lathyrus venosus and Lathyrus japonicus. They mine the leaves of their host plant. The mine is tentiform partially folding the leaflet. References Lithocolletinae Leaf miners Taxa named by Annette Frances Braun Moths of North America Lepidoptera of the United States Lepidoptera of Canada Moths described in 1929