Fig. 2. Ultra-black butterfly scales are widespread and morphologically diverse.

A sub-family level phylogeny of butterflies adapted from ref. ²² showing the distribution of ultra-black coloration and SEMs of the underlying nanostructures. Note the variation in hole shape and size including a honeycomb (a), large and small rectangles (c–f), and chevron-shaped holes (b). Subfamilies shown in gray have no known ultra-black representatives. All scale bars are 1 µm. Color of frames corresponds to color of sub-family on the phylogeny. Additional images in Supplementary Fig. 1. Species: a Trogonoptera brookiana (male), b E. chlorocroa, c C. antinoe, d H. doris, e E. dufresne, f E. klugi.