Climatic niche stability, refugial dynamics and extinction risk in Irano–Turanian mountain geophytes under future climate change

Mountain systems of Central Asia represent major centres of plant diversification, yet the evolutionary and climatic determinants of vulnerability in this region remain poorly understood. Here, we integrate phylogenetic reconstruction with ecological niche modelling and climate refugia analysis to evaluate species-specific responses to projected warming in nine taxa of Gagea sect. Gagea distributed across the Pamir–Alay and western Tian Shan systems. Maximum Likelihood analyses based on nrITS and plastid markers reveal that the focal taxa represent multiple independent evolutionary lineages rather than a single recent radiation. Ecological niche models constructed in MaxEnt show high predictive performance (AUC > 0.93 across taxa) and identify winter temperature regimes and climatic seasonality as dominant niche axes. Future projections under mid- and late-century climate scenarios indicate pronounced interspecific asymmetry in range dynamics. While several taxa are predicted to undergo elevational redistribution with moderate climatic stability, others exhibit severe contraction. Refugia analysis under late-century projections reveals a clear vulnerability gradient, with only 11% of current suitable habitat retained in Gagea praemixta and 40% in G. calyptrifolia , contrasted with > 85% retention in G. brevistolinifera and G. lutea . Importantly, climatic vulnerability does not strictly follow phylogenetic relatedness or present-day range size, highlighting the role of lineage-specific ecological specialization. The Pamir–Alay and Tian Shan mountain systems function as conditional climatic refugia, but buffering capacity is species-dependent and limited for moisture-sensitive taxa. Our results demonstrate that integrating evolutionary history with spatial modelling provides a mechanistic framework for assessing extinction risk in montane biodiversity hotspots. Such approaches are essential for identifying conservation priorities in Central Asia, where hidden evolutionary diversity may be disproportionately impacted by accelerating climate change.