Resurrection and emended description of Gastrodia foetida (Orchidaceae)

Abstract

This paper presents a re-evaluation of the taxonomic identity of Gastrodia foetida based on molecular and morphological data. The taxon was described from Iriomote Island, Ryukyu Islands, Japan, and has often been treated as a synonym of G. nipponica from Wakayama Prefecture, Honshu, Japan. In contrast, we showed that the genetic divergence between G. foetida and G. nipponica is much more significant than that between G. foetida and G. takeshimensis. Additionally, G. foetida can be distinguished from G. nipponica by a few morphological traits, particularly a more dilated column toward a little below the middle. Therefore, we propose that G. foetida is recognized as a distinct species based primarily on molecular phylogenetic evidence followed by morphological evidence. Our investigation strongly suggested that these species exhibit distinct geographic separation: G. nipponica is restricted in mainland Japan (north of the Ryukyu Islands), whereas G. foetida is mainly distributed on the more southern areas (the Ryukyu Islands and possibly Taiwan).

A novel nursery pollination system between a mycoheterotrophic orchid and mushroom‐feeding flies

“…Consequently, my focus was on Gastrodia foetida (Figure 1A–C), whose succulent flowers could potentially serve as a food source for larval nutrition. As its specific name indicates, G. foetida emits a somewhat unpleasant musty or fermented scent that is probably attractive to duped fungivorous insects (Koidzumi, 1940; Suetsugu et al, 2023). Therefore, the floral biology of G. foetida was examined on Yakushima Island, part of the Ryukyu Islands in Japan, concentrating on the possibility of the first evidence for nursery pollination, where decaying floral tissues serve as the reward, in the family Orchidaceae.…”