Mapping the unknown: Dark diversity and Wallacean gaps in Neotropical bats (Mammalia: Chiroptera)

The Wallacean shortfall remains a critical barrier to understanding Neotropical bat diversity, with most regions still severely under-sampled. Here, we combine spatial modeling, dark diversity analysis, and beta diversity components (Local Contributions to Beta Diversity – LCBD and Species Contributions to Beta Diversity - SCBD) to identify knowledge gaps and priority areas for bat inventories across the Neotropics. Our results reveal widespread sampling biases, with hotspots of data concentration surrounded by vast under Sampled regions, particularly in the Southeastern Amazonian dominion and transitional zones. Areas with high environmental dissimilarity and rapid land-use change harbor high probabilities of undocumented species occurrences. We also show that local contributions to beta diversity are strongly correlated with sampling effort, reinforcing the need for systematic field surveys in neglected regions. Furthermore, our findings highlight the role of indigenous and local communities as strategic partners in biodiversity monitoring, especially under climate-driven range shifts. We argue that integrating traditional ecological knowledge with innovative tools and targeted policies is essential to overcome sampling shortfalls. This approach is vital for detecting rare or endemic taxa, improving conservation planning, and ensuring that the ecological functions provided by bats, such as pest control and pollination, are maintained in the rapidly changing Neotropics.