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We report toughening mechanisms previously unobserved in unmineralised cuticle such as crack deflection, fibre and laminate pull-out and crack bridging and provide insights into the effects of hierarchical microstructure on crack propagation. This technique allows lamina to be isolated despite being convex, which limits 2D analysis of microstructure. Statement of Significance: We present the first comprehensive study of the damage and toughening mechanisms within arthropod cuticle in a 3D time-lapse manner, using X-ray nanotomography during crack growth. We highlight lessons to be learned in the design of engineering structures from the toughening methods employed. We find that its hierarchical pseudo-orthogonal laminated microstructure exploits many extrinsic toughening mechanisms, including crack deflection, fibre and laminate pull-out and crack bridging. Here we use non-destructive, time-lapse in situ tensile testing within an X-ray nanotomography (nCT) system to visualise crack progression through dry beetle elytron (wing case) cuticle in 3D. This desirable combination of properties results from a hierarchical structure, but we currently have a poor understanding of how this impedes damage propagation. It is very stiff and tough whilst being lightweight, yet it is made of rather ordinary constituents. Arthropod cuticle has extraordinary properties.