Meet the Cecropia Moth, the Largest Moth in North America

Cecropia moth

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Butterflies get all the love, but the cecropia moth (Hyalophora cecropia) is well worth some admiration, too.

While the sight of a monarch or a painted lady can set human hearts aflutter, moths are often dismissed as a drab nocturnal nuisance—something that exists only to engulf porch lights and invade personal space. However, it's worth it to look past moth mythology and see these strange insects with fresh eyes. This article reveals all there is to know about the large, magnificent cecropia moth.

Description and Habitat

Featuring a wingspan of up to 7 inches, the cecropia moth is the largest moth in North America. The moths have red colored bodies with wings that are black, white, red, and sometimes tan. Cecropia moth caterpillars, on the other hand, are born black and then grow to be green, with four reddish knobs and 16 yellow ones.

Cecropia moths naturally occur in hardwood forests from the Rocky Mountains to the Atlantic coast, ranging as far north as Nova Scotia and as far south as Florida. Similar to most moths, cecropia moths don't really cause trouble for people, aside from crowding lights in spring and early summer.

Adult moths only live for a few weeks and are incapable of eating, since the sole purpose of their life stage is to mate and lay eggs. The caterpillars are also harmless, and despite feeding on leaves all summer, their naturally low abundance prevents significant damage to plants.


Low population density can be a problem when looking for love, so male cecropia moths rely on their powerful senses to sniff out a female's pheromones (males can actually detect females from more than a mile away). Some bolas spiders can mimic the pheromones of a female cecropia moth, thus luring unsuspecting suitors into their clutches.

After the surviving moths partner up and mate, a female can lay more than 100 eggs, which she attaches in small groups to the leaves or stems of various host plants. Those eggs should hatch within one to two weeks, releasing larvae that then go through a series of life stages known as "instars," changing from black to yellow to green as they expand in size.

At the end of summer, the full-grown, roughly 5-inch-long caterpillar will seal itself in a cocoon. An adult cecropia moth will emerge the following spring, immediately plunging into the fast-paced world of adulthood. If you're lucky enough to see one, just sit back and enjoy its beauty—and maybe turn off your porch light.

Frequently Asked Questions
  • How big is the cecropia moth?

    The wingspan of a cecropia moth is about seven inches.

  • Where do cecropia moths live?

    Cecropia moths live in hardwood forests throughout Canada and the U.S. They can be found east of the Rocky Mountains, all the way down to Florida.

  • Are cecropia moths rare?

    The cecropia moth hasn't been assessed by the International Union for Conservation of Nature, but it doesn't seem to be too rare of a find in the U.S. You can sometimes catch one in the spring or summer, perched on a maple or birch tree.

  • What do cecropia moths look like?

    Cecropia moths have red bodies with white stripes and wings that vary in color from rust to brown to black with white, red, and tan bands. The edges of the wings are usually tan.