A tarantula with 4" leg span, reddish abdomen with a darker front end, and dark brown to black cephalothorax. There appear to be lighter bands on the legs at the joints. In the following night photos, Photo #1 has emerged from its burrow to hunt, while #2 is the same spider just before emerging. #3 is a different specimen, but I think it is the same species, standing next to its burrow.
The grounds around the lodge, situated on the north bank of the Amazon River, had numerous tarantula holes, making it easy to go out at night and spot them.