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Inter-related mechanical, thermal, and optical macroscopic properties of biomaterials are defined at the nanoscale by their constituent structures and patterns, which underpin complex functions of an entire bio-object. Here, the temperature diffusivity of a cicada (Cyclochila australasiae) wing with nanotextured surfaces was measured using two complementary techniques: a direct contact method and IR imaging. The 4–6-μm-thick wing section was shown to have a thermal diffusivity of α_⊥ = (0.71 ± 0.15) × 10^–7 m²/s, as measured by the contact temperature wave method along the thickness of the wing; it corresponds to the inherent thermal property of the cuticle. The in-plane thermal diffusivity value of the wing was determined by IR imaging and was considerably larger at α_∥ = (3.6 ± 0.2) × 10^–7 m²/s as a result of heat transport via air. Optical properties of wings covered with nanospikes were numerically simulated …