Zebra Longwing

Heliconius charithonia vazquezae, Nymphalidae
Celestún, Yucatán, Mexico
Nikon D5100, 70-300 mm f/4.5-5.6
January 29, 2020

This photo nicely shows off the pseudopupils (dark spots) in the compound eye. These pseudopupils vary between different groups of butterflies and provide a window into the inner structure. They can even be used to look for differences among ommatidia (Stavenga 2002). This blog post gives the best and most accesible summary about pseudopupils I’ve ever read.