This beautiful boa is about nine feet long and four inches+ wide at its thickest point. It had just started its molt, and the skin on its head was becoming detached (see eye in photo #5). The spots near its tail are colored brightly, resulting in its alternate name, Red-tailed Boa.
It wandered out of the rain forest one night (the three dark photos) onto the lodge grounds where I was staying along the Amazon River, and bagged until morning so that guests could see it when it was released, unscathed, the next day (#1 photo above).
This is one of the few species whose common name, Boa constrictor, is the same as its specific name.