I have shot in subtropical rainforest and there are 2 key issues:
* weather resistance (WR) and
* low light conditions.
You want to have a WR camera and some WR lenses. However, for the lens, I found that some solid lenses can also work very well (eg my Voigtlander Nokton 58mm).
For low lights, you want to have at least one large aperture lens, typically a fast prime f1.4. In addition, if you are to shoot at dusk, dawn and night, take a MF lens. In very low light, MF is much, much better than AF.
There are off course other issues:
- you need some waterpoof containers/bags; I often have a hard plastic waterproof box to store my camea and lenses, and a small rainproof carry bag
- take enough batteries
- MF lenses use less energy and keep your camera battery running longer
- take a large enough SD card (of good quality).
Hope that the comments will help...