What is "oeneis"

Oeneis (the arctics or graylings) is a butterfly genus of the Satyrinae. All but one of its members are arctic, subarctic or high-altitude alpine in distribution. Some of the members of the genus are among the butterflies that can get along in the harshest climates of any butterflies. Four species in Europe, more are found in arctic Russia, Siberia, Mongolia, arctic North America and the Rocky Mountains. Curiously, there are no observations from Greenland. The development of most species takes 2 years.