Ptarmigan

Lagopus is a small genus of birds in the grouse subfamily commonly known as ptarmigans . The genus contains three living species with numerous described subspecies, all living in tundra or cold upland areas. The genus Lagopus was introduced by the French zoologist Mathurin Jacques Brisson in 1760 with the willow ptarmigan (Lagopus lagopus) as the type species. The genus name Lagopus is derived from Ancient Greek lagos (λαγος), meaning "hare, rabbit", + pous (πους), "foot", in reference to the feathered feet and toes typical of this cold-adapted group (such as the snowshoe hare). The specific epithets muta and leucura were for a long time misspelt mutus and leucurus, in the erroneous belief that the ending of Lagopus denotes masculine gender. However, as the Ancient Greek term λαγωπους is of feminine gender, and the specific epithet has to agree with that, the feminine muta and leucura are correct.

Source: Wikipedia