The 3 can only be produced in the Mediterranean biome. This biome is known to have dry and wet weather. However, the summer seasons in this biome is very dry and usually lasts longer. Hence, the vegetation is found to be drought resistant. The 3 plants mentioned are known to be naturally drought resistant, hence it is in this biome that it thrives and survives best.
it would be kind of an advantage as they breathe air and just stay on land and to get food it can go into the water