Caiman
At night, we rowed out with some guides and swept the river banks with flashlights, looking for eyes staring back at us. Caimans have shiny eyes, and (apparently) you can reach down and grab them while they're blinking.
a Spectacled Caiman
They're lovely little reptiles. And sloths are absolutely adorable.
You really don't understand sloths at all until you seem them up close: they're built a lot like primates but they aren't related. They're related to armadilloes and anteaters, they just wind up with a similar body plan because it makes sense for living in trees. I suppose they look at us as a strange kind of tree that they can try hugging -- because, when you're a sloth, tree hugging is what you do.