Mapping the limits of trap construction: LiDAR quantification of substrate moisture effects on pit construction and quality morphometrics in Myrmeleon larvae

We examined the effect of substrate moisture on pit construction in Myrmeleon larvae across four treatments (0.0–1.5%). Construction success, pit diameter, and slope angle were quantified using LiDAR-derived morphometrics and analysed via χ² and ANCOVA. Increasing moisture significantly inhibited construction and reduced pit dimensions, with failures restricted to ≥1.0% moisture. These results suggest a critical threshold in substrate suitability, highlighting potential climatic sensitivity within this unique predatory guild.