You want evidence that
Cattleya percivaliana can grow as a lithophyte…
Here it is:
http://canaimaorchids.com/wp-content...1/DSC_0102.jpg
I got curious about your question and wanted to find any in-situ photos.
I found one.
In the photo is the owner of Canaima Orchids with a colony of
Cattleya percivaliana.
What kind of rock it is - again, I don't know for certain.
---------- Post added at 09:24 PM ---------- Previous post was at 08:15 PM ----------
I still don't know with 100% certainty what kind of rocks
Cattleya percivaliana grows on, but I have reason to believe it might be some sort of igneous rock, (rocks of volcanic origins) - probably some kind of granite, idk.