Spatial patterns and conservation gaps of Fritillaria species in China

The genus Fritillaria , a well-known Chinese traditional medicine used for over 2000 years, is primarily distributed across the temperate regions of China and is one of the threatened genera due to climate change, habitat loss, and excessive harvesting. These perennial bulbous plants are important for their ornamental beauty and traditional medicinal uses. To provide a scientific guide for Fritillaria conservation, this study explores the diversity patterns of 21 species across China using three diversity indices (species richness (SR), weighted endemism (WE), and β-diversity) with a spatial resolution of 100 X 100 km ² . The top 5% richness and complementary algorithms were used to identify diversity hotspots and conservation gaps were recognized by overlapping the diversity hotspots with Chinese nature reserves. Our results indicate that Fritillaria SR and WE are high in central and southwestern China, particularly in Sichuan and Yunnan provinces. The β-diversity is scattered across these regions, suggesting different species compositions among grid cells. We identified 145 grids as diversity hotspots for Fritillaria species in China, with significant overlap in Sichuan and Yunnan. The first-level diversity hotspots include over 70% of the Endangered (EN) and Vulnerable (VU) Fritillaria species and are the priority areas for conservation. However, only 24% of the diversity hotspots fall within nature reserves, and many regions, especially in Zhejiang, Guizhou, and Fujian, have less than 20% of diversity hotspots covered by protected areas. Using multiple diversity indices and algorithms, our study identifies critical diversity hotspots and conservation gaps for Fritillaria species in China. These findings provide a scientific basis for targeted conservation strategies to protect these valuable plants and their habitats, particularly in regions with high biodiversity and significant conservation gaps.