New combinations in the genus Didymoplexis (Orchidaceae; Epidendroideae; Gastrodieae), with a new variety of D. siamensis from Amami-Oshima Island, Japan

A new variety of the mycoheterotrophic orchid Didymoplexis siamensis, distinct from its mainland Asian relatives, has been identified on Amami-Oshima Island, Japan. This discovery challenges previous taxonomic classifications by distinguishing it based on morphological traits such as long recurved stelidia and the absence of a column foot, which had previously been used to separate Didymoplexis from the closely related genus Didymoplexiella. The study synthesizes historical and modern taxonomic research to reclassify species within these genera, providing a refined framework for their identification. The findings contribute to the understanding of orchid diversity in UNESCO-listed islands, including Amami-Oshima, Tokunoshima, Iriomote, and northern Okinawa.

SUETSUGU, K., & HSU, T.-C. (2019). New combinations in the genus Didymoplexis (Orchidaceae; Epidendroideae; Gastrodieae), with a new variety of D. siamensis from Amami-Oshima Island, Japan. Phytotaxa, 388(2). https://doi.org/10.11646/phytotaxa.388.2.4