Plant species likely to be extinct

Abstract

Understanding plant extinctions is crucial for effective conservation planning because they pose risks to other organisms, ecosystems, and human well-being. In the present study, we highlighted plant species that are likely to be extinct by analyzing all plant species categorized by the IUCN Red List as Critically Endangered with “Possibly Extinct” tags (CR (PE)). Our aims are to provide data on i) plant species likely extinct, ii) their distribution across regions, ii) threats to these species, and iv) their protection. After screening for rediscovery, synonymization with extant taxa, and presence in ex-situ collections, we recorded a total of 474 species categorized as CR (PE). The majority (93.25%) of the species were assigned to the CR (PE) category using criterion B of the IUCN Red List Criteria, which is primarily based on the species’ geographic range. The plant family with the highest number of likely extinct species was Lauraceae with 74 species. These likely extinct species were mostly trees reported to be found in the tropics, including islands. The most prominent threat that placed plant species into the CR (PE) category was habitat degradation and conversion. Clear understanding of extinction status is crucial for effective conservation planning. Therefore, comprehensive assessments, including targeted surveys and probabilistic modeling, should be carried out. This will help determine which species are genuinely CR rather than Extinct (EX), ensuring that conservation actions, when implemented, are truly impactful.