[lwcamp]

I saw this article
https://phys.org/news/2019-04-bunyip...creatures.html
and the description of mythological Amazonian critters made me think of your setting. For example:

Similar mythical creatures are associated with Brazilian cacimbas (waterholes). One of the best-known is the mapinguari, a massive biped (walks on two legs) with long sharp claws, likely to be based on memories of a giant sloth that became extinct about 12,000 years ago.

In other parts of Brazil, there are stories about the Cobra Grande, a giant snake that slides beneath the ground surface, furrowing it as it winds its way, but then also shattering it when it turns abruptly, causing earthquakes.

So ingrained in Brazilian culture is this giant snake that an annual festival in Pará State occurs with the intention of calming the snake and protecting local people from calamity. The parallels with the behaviour of the rainbow serpent in Australian traditions are remarkable.

Luke