However it was not documented much.  Like Wrightea, it might be common in Thailand (?).
If anyone knows more about this, hope to share the knowledge.

November 1999

Here is better description for Pereskia;

This is the most primitive genus in the Cactus family.  
It probably resembles the original plants that all the other cacti developed from.  
I think it is the only cactus family member with true leaves.  
The other species have lost their leaves as they adapted to drier climates and drier growing places, like the 'orchid cacti' that live on the branches of trees in the South American rain forests.

February 2000

- Beverly Erlebacher