Mapping knowledge dark spots to identify priorities for threatened and neglected taxa

Global biodiversity is increasingly threatened by environmental change, yet scientific attention remains unevenly distributed across taxa. We applied a multidimensional framework to 1,327 bat species and identified ~21% as “dark species” and 19 countries as “dark spots” across all knowledge indicators. Knowledge was disproportionately concentrated in the Nearctic and Palearctic, whereas species in the Indomalayan, Afrotropical, and Austral-Oceanian regions remained broadly under-documented across indicators. These deficits were greatest in lower-income, bat-rich countries, revealing a “Knowledge–Conservation Paradox” in which scientific attention and biodiversity data are scarcest where conservation needs are greatest. Our reproducible framework provides a transferable approach to identify hidden knowledge shortfalls and direct research, monitoring, and data mobilization toward the species and regions that need them most.