The bird is called in Spanish cacique lomiamarillo or paucar. Its Latin name is Cacicus cela. In English it's called a yellow-rumped cacique. In [one representation of] Tikuna/Magüta, it's called káurë. It's the gorgeous black bird with the blue eyes and the yellow on its wings and tail that I put a picture of when I posted about the story. Here's its English-language wikipedia page, which has some other photos.