https://phys.org/news/2018-06-poisonous-moths.html

While smaller and paler red forewing markings were associated with more cyanide in females, size and brightness of wing colour were no guide to cyanide levels in males.

"Many animals use aposematism (warning colouration) to tell predators it would be better to find lunch elsewhere," said first author Emmanuelle Briolat, of the University of Exeter.