Apollo Parnassius apollo

This mountain butterfly has earned international protection — it is one of the very few insects listed on CITES Appendix II, meaning international trade in wild specimens is regulated by treaty. Found only on high-altitude meadows and rocky slopes, it's vulnerable to habitat loss, climate warming, and the attentions of collectors. The red eyespots on white wings are a genuine warning: caterpillars feed on stonecrop plants containing compounds that persist and make adults mildly toxic to predators.

The female carries a unique anti-mating device: after her first mating, the male deposits a waxy plug called a sphragis that physically prevents her from mating again. This structure, visible on museum specimens, is unique among European butterflies and makes females instantly distinguishable from males in any collection.