Orchidaceae subf. Apostasioideae comprises the genera Apostasia (7 spp.) and Neuwiedia (8 spp.). They are not always included in Orchidaceae s.str., but are traditionally regarded as "the most primitive orchids". Recent phylogenetic analyses of morphological and molecular data place them as sister group to the remainder of Orchidaceae. Orchids are easily recognized on distinct floral characters, but several authors have pointed out that characteristics like the gynostemium, pollinia etc. make sense only in connection with the unique seedling biology with an obligate mycotrophic protocorm stage. Protocorms of spontaneous Neuwiedia veratrifolia seedlings have been found at three locations, and the mycobiont was subcultivated from live pelotons. The typical orchid mycorrhizal infection pattern with newly infected cells in the outer cortex and older degrading pelotons in the inner cortical cells was observed. The preliminary examination of the fungal endophyte categorizes it as typical orchid mycorrhiza belonging to the group of Rhizoctonia-like endophytes.

Key words: Neuwiedia veratrifolia, orchid mycorrhiza, orchid phylogeny, Orchidaceae, protocorm