The 3 species to the genus Zanda have been variously regarded as two, then as one species for very some time. Inside a 1979 paper, Australian ornithologist Denis Saunders highlighted the similarity between the small-billed in addition to the southern race xanthanotus about the yellow-tailed and addressed them as 1 https://cockatooumbrella97261.madmouseblog.com/17102149/an-unbiased-view-of-where-can-i-find-a-umbrella-cockatoo