Invertebrates
Question Mark Butterfly
Polygonia interrogationis · also called question mark
A butterfly resting on a tree trunk with its wings closed looks for all the world like a dry, curled dead leaf, and only a close look at the underside of its hindwing reveals the tiny silver punctuation mark, a curved dash and a dot, that gives the question mark butterfly its name.
Overview
The question mark butterfly, Polygonia interrogationis, is native to forest and woodland edge habitat across a broad range of eastern North America. Its distinctive silver underwing marking, convincing dead-leaf camouflage at rest, and unusual adult diet of sap, fruit, and dung rather than flower nectar make it one of the more visually and behaviourally distinctive butterflies in eastern forests.
A name hidden until the wings close
Only visible on the closed underside of the hindwing, the tiny silver question mark that gives this species its name stays completely hidden during flight, revealed only once the butterfly settles and folds its wings against a tree trunk or leaf litter.
Status
Least Concern — widespread and stable across suitable forest and woodland edge habitat throughout eastern North America.
Question Mark Butterfly: common questions
Why is it called a question mark butterfly?
The underside of each hindwing carries a small silver marking made up of a curved dash and a separate dot positioned just below it, together closely resembling the shape of a question mark, a subtle detail visible mainly when the butterfly rests with its wings closed and gives the species its distinctive common name.
How does the question mark butterfly survive winter?
This species overwinters as a fully formed adult butterfly, finding shelter in protected spots such as tree bark crevices or loose bark rather than migrating to a warmer climate or dying off at the end of the season, allowing it to emerge again and resume activity as soon as temperatures warm sufficiently in spring.
What does the question mark butterfly eat as an adult?
Unlike many butterflies that rely mainly on flower nectar, the adult question mark more commonly feeds on tree sap, rotting fruit, and even animal dung, a diet shared with several closely related anglewing butterflies and one that provides different nutritional resources than nectar alone.
How does the question mark butterfly camouflage itself?
With its wings closed, this species closely resembles a dry, curled dead leaf in both shape and colouration, an effective camouflage strategy that helps it blend into leaf litter or tree bark and avoid detection by predators while at rest between flights.