Uncovering the Chemosensory Repertoire of Ips typographus Larvae: Gene Expression Profiling The Eurasian spruce bark beetle (Ips typographus) is a major pest in European and Asian spruce forests, with larvae directly contributing to phloem degradation and tree mortality. Despite extensive studies on adult chemosensation, larval sensory biology remains largely unexplored. Here, we profile chemosensory genes in first- and third-instar larvae. High-throughput RNA sequencing of larval heads is being used to quantify expression and reveal larval-specific chemoreceptors. Comparisons with adult profiles will uncover developmental shifts in chemosensory function, providing a foundation for functional characterization and enhancing our understanding of larval sensory ecology in this ecologically and economically important species.