Fig. 1

The African Flower Scarab (Eudicella gralli). a Photograph of a female Flower Scarab. The iridescent coloration is caused by optically active layers within the cuticle. Spectroscopic investigation of the surface chemistry of the scarab cuticle is challenging, because of the curvature and multilayered complexity of the material. b Details of the front part of E. gralli and the dorsal head protrusion used to dig through soil