Gynaephora is a genus of tussock moths in the Erebidae family. They are mainly found in the Arctic and Subarctic region and are best known for their unusually long larval development period. The life cycle of G. groenlandica was once believed to take 14 years, but subsequent studies reduced it to 7, a slow development rate that is extremely rare in the Lepidoptera. The caterpillars have five instars, with each instar lasting a year.