Abstract
Ophioglossum is an herbaceous genus of the Ophioglossaceae family with notable medicinal value and ecological importance in forest ecosystems. However, the impact of rising global temperatures on its distribution and the habitat ranges of its species in China remains unclear. This study assessed the potential distributions of five closely related Ophioglossum species under current and future climates, identified key environmental drivers, and compared the predictive performance of MaxEnt and GARP models to support conservation planning. Distribution models were built using occurrence records and environmental variables, with key factors identified through jackknife tests and response curves; performance was evaluated using AUC. Future projections were based on CMIP6 scenarios (SSP126, SSP245, SSP370, SSP585). Both models showed good predictive ability (AUC > 0.84), with MaxEnt demonstrating higher efficiency and stability. Species exhibited distinct environmental preferences: O. petiolatum responded mainly to temperature range and vapor pressure; O. pedunculosum to solar radiation and wind; O. vulgatum to vapor pressure and seasonal precipitation; O. reticulatum to solar radiation and diurnal temperature variation; and O. thermale to precipitation seasonality and soil properties. High-suitability areas are currently concentrated in Yunnan, Sichuan, Guizhou, and Hunan provinces. Future changes in suitable habitat were limited, with no significant differences between the 2050s and 2070s. Climate change is not the primary near-term driver of distribution shifts for these species; greater threats arise from habitat fragmentation, human disturbance, and reproductive constraints. Conservation efforts should prioritize enhancing habitat connectivity and protecting microhabitats in existing high-suitability regions. This study provides a scientific basis for Ophioglossum conservation, and future work should incorporate population dynamics and dispersal mechanisms to improve predictive realism.