Hexagonal‐Close‐Packed Colloidal Crystals in <i>Glenea celestis</i> Beetles

Colloidal crystals reflecting interference‐based structural colors have been reported in many organisms, but are yet to be accurately described. Herein, the bright, iridescent scales of green and blue Glenea celestis beetles investigated using optical ultrastructural techniques. The studies based on focused ion‐beam scanning electron microscopy synchrotron small‐angle X‐ray scattering data reveal origin stem from previously undocumented hexagonal‐close‐packed colloidal within their scales. properties various structures full‐wave simulations. results highlight need for further research regarding development color beetles.