Résumé
Orchidaceae, one of the largest plant families, have been predicted in several analyses to be under a higher level of threat than angiosperms as a whole. Despite this, compared to many other major groups of animals and plants, orchids are under-represented on the Red List of the International Union for the Conservation of Nature (IUCN). Since 2000, concerted efforts have led to the number of orchids on the Global Red List increasing from eight to > 2,000 species, but many of these assessments are now outdated, and
c.
28,000 species remain to be assessed for the first time. Here we review the current knowledge of the conservation status of orchids based on Red Listing and other methods, including machine learning and EDGE (Evolutionarily Distinct and Globally Endangered). At the geographical level, Sub-Saharan Africa is relatively well sampled for the Global Red List, whereas South and Central America and tropical Asia are poorly sampled. With the existing Red List assessments, levels of threat vary widely between tribes and subtribes. Tribes and subtribes with no or low sampling are identified. We discuss the main threats, and we identify climate change and fire as emerging threats, the former due to the potential for disruption of critical associations with pollinators and mycorrhizal fungi.