Not an orchid but I'm sure one of you will have the answer:

[harrywitmore]

This is in fact Dischidia vidalii. pectinoides is a synonym. I have a number of Dischidias species and only a few develop these types of bullate leaves. Dischidia major is another. I've been growing then for 10 years and never had an ant take up housekeeping. This are not native to Central or South America but the South Pacific islands such as Indonesia, Phillipines, Australia, Malaysia, etc.

[Mahon]

Originally Posted by harrywitmore

This are not native to Central or South America but the South Pacific islands such as Indonesia, Phillipines, Australia, Malaysia, etc.

I knew they were native to Asia, but thought they may have also been distributed in the Americas. I will have to find the picture of the large plants in situ in the rainforest... perhaps it was a relative of Dischidia then?

-Pat