The White-headed Flightless Steamer Duck or Chubut Steamer Duck (Tachyeres leucocephalus) is endemic to Argentina.
It is the most recently recognized species of steamer duck, being described only in 1981. This is because it is only found along a rather small and sparsely populated stretch of coast around the Golfo San Jorge in southern Chubut and northern Santa Cruz Provinces, and that steamer ducks in general look fairly similar in plumage.