what is the golden crowned sifaka?
It is a medium-sized lemur.
Golden-crowned sifaka
The golden-crowned sifaka or Tattersall's sifaka ("Propithecus tattersalli") is a medium-sized lemur characterized by mostly white fur, prominent furry ears, and a golden-orange crown. 
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Golden-crowned sifaka [SEP] Introduction
The golden-crowned sifaka or Tattersall's sifaka ("Propithecus tattersalli") is a medium-sized lemur characterized by mostly white fur, prominent furry ears, and a golden-orange crown. It is one of the smallest sifakas (genus "Propithecus"), weighing around and measuring approximately from head to tail. Like all sifakas, it is a vertical clinger and leaper, and its diet includes mostly seeds and leaves. The golden-crowned sifaka is named after its discoverer, Ian Tattersall, who first spotted the species in 1974. However, it was not formally described until 1988, after a research team led by Elwyn L. Simons observed and captured some specimens for captive breeding.