The MO Name “Mycoheterotroph” is an MO pseudo-order representing plants which are obligatory mycoheterotrophic on macrofungi. Many are in the genera Ericaceae and Orchidaceae.
For a much longer list of genera see "New Phytologist (2010) Special Issue on Mycoheterotrophy. 185(3) 591-864 https://doi.org/10.1111/j.1469-8137.2009.03151.x
At least 49 plant species are fully mycoheterotrophic. V. Merckx. 2012. Mycoheterotrophy: The biology of plants living on fungi, p.4 & Table 7.1. See also Darvin DeShazer, Species List: Mycoheterotrophic Plants
I hadn’t found that great species list.
Undeprecated and changed to a pseudonym to better capture the intent of the Name, and to create a convenient place to add a list of species (rather than an MO “Species List”, which is actually a list of Observations).