With unique and beautiful flowers, the slipper orchids Paphiopedilum spp. have always been popular in horticulture. Conservation of the genus faces serious challenges, however, as they may be collected by orchid enthusiasts and the species are rare in the wild. Paphiopedilum gratrixianum Rolfe has a disjunct distribution in southern China, Laos, Thailand and Viet Nam. It is categorized as Endangered on the Red List of Biodiversity–Higher Plants of China, as Critically Endangered on the IUCN Red List of Threatened Species, as a first-rank plant for national key protection in China, and as a Plant Species with Extremely Small Populations by the Yunnan provincial government in 2021.
In 2021 a population of c. 150 mature individuals of P. gratrixianum was discovered in Zhenyuan County, Yunnan Province. With the support of the Yunnan Plant Species with Extremely Small Populations conservation programme (2021S14X-09), we carried out further surveys for the species in April 2022 and October 2023. We discovered the species in two additional localities: c. 200 individuals in Shiping County, Honghe Autonomous Prefecture (> 150 km from Zhenyuan) and c. 150 individuals in Mojiang County, Pu'er City (> 80 km from Zhenyuan). All of the c. 500 individuals now known in China occur outside protected areas. With a narrow distribution range and low numbers, P. gratrixianum requires urgent priority conservation. During our surveys we collected some seeds and we are now attempting to cultivate seedlings for ex situ conservation and scientific research, at Kunming Botanical Garden.
An additional, previously known population of P. gratrixianum in Xinping County, Yunnan, became extinct in 2019 as a result of overcollection. Priority conservation actions are required to prevent the similar extinction of the three known extant populations, including establishment of in situ conservation sites, increasing publicity and law enforcement efforts, and development of artificial propagation and in vitro preservation technologies. Further surveys are also required in southern Yunnan and adjacent areas, along with research on the genetic diversity, pollination ecology and seed germination of the species.