Do all amphibians belong to the class reptilia?

No because the amphibian group is found in specific areas much different then the reptile. also the reptile has a different look and shape to its body!Amphibians have an almost slimy look to their bodies and must always live very very close to water. Reptiles have a rough texture to their bodies and can live in places like the desert and get along fine with very little water. Reptiles almost always have tails this is not true with amphibians. As you can see they are very different and should not be grouped together.