Chimeras are a certain group of Zoid types. The name originated from an animal in Greek Mythology, that was part snake, part goat, and part lion. However, in Zoids, there are actually no Chimeras of this type, thus we can say that a "Chimera" in Zoids is basically just a combined animal. None of the Chimera's specific animal inspirations have been explicitly revealed, but some of them can be inferred from the designs and names.
All of the combinations are pure speculation.