Listed are some of the many biomes that you can discover with Biomes O' Plenty
Although the Mod states there are around 60-90 biomes (Depending on what version you're using), there are over 110 ".class" files which are used to generate the biomes. Some of them are the Terrain Generations, nerfing the vanilla biomes also give another class files, so it's basically 87 biome is correct without the vanila biome nerfed and the Terrain Generations. Technical biome also counts, including beaches replaced by gravels, ponds etc.
For a more detailed list with Images and Descriptions, visit Biomes List.