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I don't know much about Optuni so I cannot answer on that specifically, however they do have some types of cacti (such as prickly pear) in their natural environment. The entire range they live in isn't all rainforest

They are typically found in area with rather dry land (although humid). I fyou can find pictures of them in their natural environment, you may be able to get a better idea, you will often see them in hard, rocky terrain, etc.