Bolivian Bamboo Rat
Bolivian Bamboo Rat (Dactylomys boliviensis), Manu Wildlife Center, Madre de Dios, Peru
These large arboreal rodents are surprisingly difficult to track down. I located one by the sound of it munching on ornamental bamboo behind my cabin. Their strange territorial calls are a characteristic nighttime sound of SE Amazonia: https://macaulaylibrary.org/asset/249909.