partial and fully mycoheterotrophic orchids are fascinating. at least 1 kind is native to North america with many species(corallhiza, trifida being the most common since its a partial mycoheterotroph), gastrodia seems to be the most species rich MH.

they keep finding new thismia species(1 supposedly existed in america a century ago, but became extinct. the rest lives in South east asia, china, india, and australia area. they refind at least 2 thismia that went extinct but was found again in another area(T.kobensis, and T. neptunis). i find thismia the most fascinating one.

and South america has thier own thismia(its alleged that this is a different genus related to thismia), recently they seperated the African variety into its own family status.

I was so disappointed when I learned how hard (I mean I haven't actually tried it) to culture them, but it makes sense given how they occur.