Butterflies in the Polygonia genus share a distinctive mark: a white arc on their brown underwings that looks like a bit of punctuation drawn with a white gel pen. Their common name is the Comma Butterfly.
Do you notice something different about the shape of this butterfly’s wings? They’re notched and ragged, rather than having a smooth curve like most lepidopterans. That’s so they more believably mimic a leaf. The irregularity gets a nod in its scientific name (Polygonia = many sided) and a second common name: anglewing.
Adults aren’t the only life stage that can hide from predators. The first three stages of the caterpillar look like bird droppings, and the cocoons are also camouflage pros—they look like dried, curled leaves.
What’s more, a 2013 study linked below found that the comma mark itself was a deterrent for birds. Researchers covered up the comma on some butterfly wings, and they found that the marked butterfly wings faced fewer bird attacks. In theory, the white mark is a distraction. I don’t love that several dozen butterflies were sacrificed for the experiment, but it’s a fairly common genus, and many would have been eaten naturally.
On the U.S. West Coast, there are several similar looking Comma Butterflies, sometimes distinguished by the black spots on their lower wings: Polygonia Satyrus, (the Satyr Comma) Polygonia gracilis (the Hoary Comma), P. faunus (the Green Comma), and P. Oreas. I’m fairly sure this is the Satyr Comma.
In case you were wondering, there is also a Question Mark Butterfly in the eastern U.S., Polygonia interrogationis. Its underwing is inscribed with a white curved line and a dot. Perhaps some other punctuation marks are out there to be discovered on the wing. Keep your eyes open for semicolons, hashtags and asterisks.
Stay curious!
See more of Karen’s work here.
Sources:
Paper that asserts the comma mark is a defensive win: https://www.sciencedirect.com/science/article/pii/S0003347213004600. Accessed 6/9/25.
Butterflies of Oregon’s description and photos of the Satyr Comma: https://www.butterfliesoforegon.com/polygonia-satyrus. Accessed 6/9/25.
All photos by Karen Richards.