Conservation Challenges for Endemic Vascular Plants: Exploring Large-Scale Patterns in Climate-Driven Distribution and Distinctive Functional Traits.

This study addresses global conservation challenges for endemic vascular plants by exploring large-scale distribution patterns and functional traits influencing their resilience, survival, and regeneration under changing environments. We compiled data for 23,981 endemic vascular plant taxa across 173 ISO countries using publicly available resources. The dataset includes conservation assessments, "Native" occurrences, and key functional traits relevant to ex situ conservation (plant life forms, seed dormancy and seed storage behavior). We analyzed climate-driven distribution patterns, trait representation, and their relationships with Red List conservation categories. Alarmingly, 58% of endemic vascular plant taxa are designated as extinct or threatened, three times the rate observed in non-endemics, highlighting a severe conservation crisis. This disproportionate threat reflects their heightened sensitivity to habitat loss, environmental changes, and climate fluctuations. Results indicate that climate-driven distribution patterns and distinctive plant and seed traits contribute to this trend. Notably, 34% of endemic taxa are "climate specialists", with 71% already threatened. Extinction risk spans 11 life forms, with over 50% of taxa within these groups currently threatened. Additionally, 91% of endemic taxa exhibit seed dormancy, requiring dormancy-breaking mechanisms for ex situ conservation. While 82% produce orthodox seeds, suitable for seed banking, this is 10% below the global average. A greater proportion of endemic taxa produce recalcitrant seeds, which cannot be conserved in conventional seed banks and require alternative approaches, such as cryopreservation. Conservation strategies must consider the climate relationships and functional traits that influence plants' resilience. Priority should be given to "climate specialists", taxa with narrow climate ranges, and those representing susceptible life forms or producing recalcitrant or dormant seeds, which complicate ex situ conservation. Enhancing seed banking strategies to accommodate seed trait variations is essential for long-term conservation success. Continued research into the storage and propagation of recalcitrant and/or dormant seeds is vital to future reintroduction and recovery efforts.