What is This Big Moth?

What Big Moth Might This Be?

Image result for cecropia moth
Cecropia Moth (Photo: Flicker Sharing, Charlie Kellogg)

Identifying Big Moths of the Eastern US

Around this time of year I find a lot of moth cocoons and newly emerging moths at night. I thought it would be a good time to review some of the big moths that you may find in the Eastern US, and what they look like.

What is a "big moth?" I consider a big moth to be anything with a wing span that is about 3" and more. To start with though,  you probably should know how to tell if what you're looking at is a moth or butterfly.  You can find both out in the day, though moths are mostly nocturnal or night dwelling. Here's a handy list:


  • Diurnal-come out during the day
  • Thin narrow antennae, not fuzzy
  • Thin waist
  • Abdomen is not hairy
  • Fold their wings vertically over their body
  • Brightly patterned and colored
  • Make a chrysalis, which is a hard covering over their larvae while they pupate



  • Nocturnal-come out mostly at night but can sometimes be found in daylight
  • Thick fuzzy antennae
  • Thick waist
  • Abdomen is fuzzy
  • Hold wings out straight
  • Usually less brightly patterned or colored
  • Make a cocoon covered by silk, which is often semi-soft

There are more types of moths in the world than butterflies, but most people can't tell the difference. To make things even more confusing,  some moths do fly during the day, though they are less common. Regardless, it's often the showy big moth that grabs our attention. Here's a quick gallery of what you might find in the Eastern US:

POLYPHEMUS MOTH (Antheraea Polyphemus) 4-6" Wing span

Adult Polyphemus Moth (Photo: Flicker Sharing Charlie Kellogg4)

LUNA MOTH (Actias luna) 3-4.5"

Luna Moth (Photo: Flicker Sharing, Lynette Edwards)

CECROPIA MOTH (Hyalophora cecropia) 4-6"

Cecropia Moth (Photo; Flicker Sharing, Elizabeth Sellers)

IMPERIAL MOTH (Eacles imperialis) 3-7"

Imperial Moth (Photo: Flicker Sharing, Richard Crook)

TULIP TREE SILK MOTH (Callosamia angulifera) 3-4.5"

Tulip Tree Moth (Photo: Wiki Commons, Jay Sterner)

IO MOTH (Automeris io) 2-3.5"

Io Moth (Photo: Flicker Sharing, Judy Gallagher)

ONE-EYED SPHINX MOTH (Smerinthus cerisyi) 2-3.5" 

One-eyed Sphinx Moth (Photo: Flicker Sharing, Seabrooke Leckie)

*There are a lot of different sphinx moths, this is just one example.

REGAL MOTH (Citheronia regalis) 3-5"

Regal Moth (Photo: Flicker Sharing, Richard Crook)

GIANT LEOPARD MOTH (Hypercompe scribonia) 2-5"

Giant leopard Moth (Photo: Wiki Commons, Jeremy Johnson)
I know that I'm only scratching the surface of big moths here. If I've forgotten a species or type then please e-mail me. If you're curious, the largest moth in the world is the Atlas Moth (Attacus Atlas), coming in at a whopping 9-11"! They're found in Asia though, so not the Eastern US region. Here's a picture if you're curious.

Atlas Moth (Photo: Flicker Sharing, Steve Smith)

If you'd like to learn more about big moths you can check out these books:

Peterson's Field Guide to Moths of Northeastern North America. 

Peterson Field Guide to Caterpillars.