Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada

Final: Silhouette Key to Major Moth Families

Identifying moths can be quite a task for someone not familiar with the major families. BugGuide.Net currently has over 1300 pages of moth photos available when trying to ID a moth from the U.S. or Canada. I have found that a simple key to the major families can be helpful in narrowing the search to 20 pages or less. Keep in mind: 1) the silhouettes are general in nature, and there are exceptions in each family 2) there are families not represented here 3) BugGuide.Net has several members who are very willing and able to ID most moths if you upload a photo to the moth page found here.

To use this key, simply click on a silhouette and it will take you to that section of the guide or click on the link to go to the info page.


Tortricid Moths (wingspan 8 to 35 mm)

Slug Caterpillar Moths (wingspan 10 to 35 mm)

Plume Moths (wingspan 12 to 40 mm)

Silkworm Moths (wingspan 32 to 45 mm)

Pyralid Moths (wingspan 10 to 55 mm)

Crambid Snout Moths (wingspan 10-35 mm)

Geometrid Moths (wingspan 8 to 65 mm)

Clearwing Moths (wingspan 13 to 60 mm)

Prominent Moths (wingspan 25 to 60 mm)

Tussock Moths (wingspan 20 to 70 mm)

Tiger Moths (wingspan 12 to 80 mm)

Tent Caterpillar Moths (wingspan 22 to 105 mm)

Owlet Moths (wingspan 20 to 150 mm)

Sphinx Moths (wingspan 30 to 150 mm)

Giant Silkworm and Royal Moths (wingspan 30 to 150 mm)


All silhouettes were created from photos taken by Patrick Coin or Lynette Schimming that are currently posted on BugGuide.Net.

Wingspans are from the National Audubon Society Field Guide to Insects & Spiders.(1)

How
do you turn these pictures into silhouettes?

 
photoshop
You select the outline of the moth.. this can be quite a bit of work depending on the colors involved and the background. Once the selection process is done you just paint the moth white, then you select the inverse paint the background black.

 
It might be simpler...
to select the background instead of the moth

 
Yes
either or... whichever is easier. Good point.

 
Thanks
I use GIMP, but its basically the same steps as the photoshop version.

Links
It would be nice if there were also links to the info pages of each group, for instance: Tortricid moths.

 
I agree
Done! I also noticed that with my new monitor I can see I had many different colors of black for backgrounds. I think I've fixed that now.

Moths?
Your last line from the first paragraph suggests uploading Moths to ID Request - although there may be some controversy, I would suggest that we should recommend that contributors upload directly to Moths, unless it's one of those strange-looking moths that some folks have trouble placing to order...

Re: wingspan, it would be nice to clarify this measurement. Some books use FW length. Do you mean from tip of left wing to tip of right wing? Wouldn't that be useful mainly with pinned specimens with the wings outstretched?

 
It would be good to have
a Glossary entry for Wingspan. Butterflies and moths are traditionally spread with the inner margin (trailing edge) of the forewings positioned perpendicular to the body. My guess is that "wingspan" is measured as the greatest expanse of the forewings when they're in this position, but I'm not sure.

The forewings of many moths are shaped like right-angled triangles, with the costal margin (leading edge) forming the hypotenuse of the triangle, as in this example. If the forewings were positioned so that their costal margins were perpendicular to the body, the greatest expanse would be considerably wider than described above. Maybe someone can clear this up.

 
Wingspans
above were taken from the National Audubon Society Field Guide to Insects & Spiders. I tried to find where they specifically say what their definition of wingspan is, but didn't find anything. At the time I did the article I assumed that it was when the moths are spread out like when they are pinned... and wingspan would be wingtip to wingtip.

 
Good call
on where to post the moths. I changed that. Of course back in '05 it wasn't an issue, but with our current traffic it is definitely better to post them directly to the moth page. As for wingspan, that may be a project for another day. I'll have to do some work on that. Thanks.

Could you
silhouette something like Callosamia angulifera? That has a very different shape than a Polyphemus moth.

 
I will consider that
thanks for the suggestion.

Great Job
Very nice work, Lynette. Could you add a silhoutte for this moth http://bugguide.net/node/view/192586/bgimage It looks different than the other clearwings.

great!
In John Himmelman's book "Discovering Moths" he has a silhouette page that I have used for families I was not all that familiar with. Having the direct link here at bugguide is just great!!

thanks for your work!

Not sure if it's been here long enough
for everyone to review. But if it looks good to you all....it's good enough for me.

 
A Great Resource
This has become a great resource. Last week I used it to identify a Apatelodid moth in a matter of minutes.

Wonder how we can publicize it within BugGuide?

--Stephen

Stephen Cresswell
Buckhannon, WV
www.stephencresswell.com

What do you think?
Enough families covered? Silhouettes a good representation of that family? Good enough explanation? Should there be more writing explaining certain things....like many owlets have the orbicular and reniform spots?

 
fills the gap nicely
A very good idea, Lynette, certainly helpful in narrowing down the number of places to look when trying to ID a moth. There's one other family that's not often encountered but has such a distinctive-looking posture silhouette, including it might help: Gracillariidae.

Like pictures, these silhouettes are worth a thousand words; I don't think there's any better way to quickly sort out the families.

 
How 'bout this one

That's a distinctive one that comes up pretty often.

Nice job, by the way.

 
OK
Done & thanks.

Great idea
Great idea, Lynette, this will prove very useful!

--Stephen

Stephen Cresswell
Buckhannon, WV
www.stephencresswell.com