Currently viewing the category: "Hornworms"
What's That Bug? does not endorse extermination

Subject:  What caterpillar and moth or butterfly will this be
Geographic location of the bug:  Chapala, mexico
Date: 09/15/2019
Time: 03:40 PM EDT
Your letter to the bugman:  My friend sent me a pic of this caterpillar from Chapala Mexico. After looking online I found hornworm caterpillars. Which one is this and what moth or butterfly does it turn into. Also what is the purpose of the horn?
How you want your letter signed:  Sarah

Unknown Hornworm

Dear Sarah,
We are very confident that this is a Hornworm in the family Sphingidae, and that it will eventually transform into a Sphinx Moth or Hawkmoth, but alas, we have not been successful identifying its species despite the excellent database on Sphingidae of the Americas.  We will write to Bill Oehlke to see if he can provide a species identification.

Bill Oehlke Responds.
Hi Daniel, I think I have seen that one before, but a quick check did not let me come up with an id. Later this afternoon I will send it to Jean Haxaire to see if he knows what it is.

Jean Haxaire has indicated Isognathus rimosus inclitus.
I wish permission to post it to website. Please check with photographer and forward his or her name.

Ed. Note:  The subspecies Isognathus rimosus inclitus is pictured on Sphingidae of the Americas, but there is no larval image.  We are writing back to Sarah with the identification and a request from Bill Oehlke to include the image on his comprehensive site.

Hi Daniel,
Thanks so much. I’m checking with my friend and am getting an exact location if possible. I’m sure she’ll be alright with sharing, but will get back to you tomorrow.

Hi Daniel,
Pilar Martinez is the photographer and the pic was taken in Chapala, Jalisco , Mexico
Pilar has said ok to sharing the image. I’m copying her on this email.
Thank you so much for the identification and glad to contribute to the database.
Please send us a link when it’s up.

Thanks Sarah and Pilar,
Pilar’s image is already live on What’s That Bug? and Bill Oehlke will post it to the species page for
 Isognathus rimosus inclitus on his site, Sphingidae of the Americas, where he has adult moths of  pictured, but no caterpillars.

Bill Oehlke’s website:
Hi Daniel,
Please say thanks to Sarah and Pilar for me and let them know Isognathus rimosus inclitus image has been posted to
Bill Oehlke

What's That Bug? does not endorse extermination

Subject:  What is this chunky boy?
Geographic location of the bug:  Southern Utah, Kane County
Date: 08/22/2019
Time: 01:29 PM EDT
Your letter to the bugman:  Hi! I’ve have looked and looked but cannot definitively identify this caterpillar I found a couple days ago. It was in a cottonwood tree. My first thought was a tomato hornworm but the side spots and horn seem too different. Thoughts?
How you want your letter signed:  D. E.

Big Poplar Sphinx Caterpillar

Dear D.E.,
Though this is not a Tomato Hornworm, it is a different species of Hornworm from the family Sphingidae.  We believe it is the Big Poplar Sphinx caterpillar based on the species found Sphingidae of the Americas Utah page.  According to Sphingidae of the Americas:  “Larvae feed on cottonwood and poplar (
Populus) and willow (Salix).”

What's That Bug? does not endorse extermination

Subject:  Giant Caterpillar Found!
Geographic location of the bug:  Mexico, Guanajuato State
Date: 07/30/2019
Time: 12:58 AM EDT
Your letter to the bugman :  Hi there! I was in my yard today and was shocked when I discovered this huge, mauvey colored, black striped caterpillar. I tried searching around the internet to indentify it but I had no luck. It seemed to have a single eye-like pattern in the middle of its butt, which made me think maybe it was a swallowtail, but again I can’t find anything like it. I am really interested in knowing what it is and would be so grateful if you could help! It’s also the summer/hot/rainy season here in Mexico if that helps! Thanks for your efforts!
How you want your letter signed:  Emma

Typhon Sphinx Caterpillar

Dear Emma,
The “single eye-like pattern in the middle of its butt is known as a caudal bump, a mark at the tip of the abdomen that marks the spot where a caudal horn was shed from a prior molt.  Because of that caudal bump, we correctly guessed the genus and then quickly located matching images of a Typhon Sphinx Caterpillar,
Eumorpha typhon, on Sphingidae of the Americas where it states the larval food plant is grape.  Do you have a nearby grape vine?

Typhon Sphinx Caterpillar

Wow thank you for identifying it so quickly! That’s so fascinating! We initially believed that it had fallen off from a vine that runs along our fence and into our courtyard, so that makes perfect sense. Not sure if it is a grape vine however. Yesterday I put it back on the vine, so I’m glad that’s where it wanted to be. Thank you again!

It might have left the vine to find a place to pupate.  Many Sphinx Caterpillars burrow underground to pupate.

What's That Bug? does not endorse extermination

Subject:  Huge caterpillar!
Geographic location of the bug:  Northern California
Date: 07/26/2019
Time: 03:09 AM EDT
Your letter to the bugman:  Hi,
I have never seen this large of a caterpillar ever, not in the great outdoors nor in a museum! It was happily munching on our green tomatoes. It was 3/4” thick and almost 3 inches long. Was incredible! Thank you!
How you want your letter signed:  Thanks, Aimee

Tobacco Hornworm

Dear Aimee,
Have you been growing tomatoes for many years?  Most gardeners who grow tomatoes are familiar with the Tobacco Hornworm, the larva of the Carolina Sphinx,
Manduca sexta, which feeds on the leaves and occasionally fruit of tomatoes and other related plants.  Here is a BugGuide image for comparison.

Hi Daniel,
Thank you for this! I have, but have never seen a caterpillar like this! 🙂 Are both moths and butterflies called “caterpillars” in this stage?
Thank you,
Hi again Aimee,
The larvae of both butterflies and moths are commonly called caterpillars, but some caterpillars have more specific names like the Hornworms of the family Sphingidae, the group to which your Tobacco Hornworm belongs, and that name refers to the caudal horn found on many members of the family.  After the caterpillar stage, both butterflies and moths have a pupal stage, commonly called a chrysalis for butterflies, and cocoon for a moth when the pupa is encased in a silken housing.  Generally speaking, the Caterpillars of moths are bigger than the caterpillars of butterflies, and some of the largest North American caterpillars are the Hickory Horned Devil and the Fig Sphinx caterpillar.  In Northern California, other large caterpillars you might encounter are the Polyphemus Moth Caterpillar and the Ceanothus Silkmoth Caterpillar.
Ah, I see, that is great to know. Thank you so much for your time, I really appreciate it!
What's That Bug? does not endorse extermination

Subject:  big ugly thing
Geographic location of the bug:  southern calif
Date: 07/22/2019
Time: 04:04 PM EDT
Your letter to the bugman:  hi – i flushed this beast out of my grapevines, have no clue what it is.  it has what looks like one eye on top of its head, four pairs of feet. no horn on its backend.
How you want your letter signed:  Sue

Achemon Sphinx Caterpillar

Dear Sue,
This is an Achemon Sphinx Caterpillar, a member of the family with caterpillars commonly called Hornworms.  Your particular species, in fact many members of that genus, shed their horn before attaining full size, and there is a caudal bump where the caudal horn was located.  The caudal bump does resemble an eye.

Hi Daniel – thanks so much!  I discovered the retractable head ( how weird ) when it started to move. I had it’s ends mixed up…  I hope it sticks around when it morphs.
What's That Bug? does not endorse extermination

Subject:  Caterpillar
Geographic location of the bug:  Upper Peninsula of Michigan
Date: 07/20/2019
Time: 11:34 AM EDT
Your letter to the bugman:  Hi there, we found this big caterpillar after some storms last night. We were hoping to find out what it is.
How you want your letter signed:  Cindy Occhietti

Leafy Spurge Hawkmoth Caterpillar

Dear Cindy,
Coincidentally, we just posted additional images of a Leafy Spurge Hawkmoth Caterpillar, also submitted from the Michigan peninsula.  Do you by chance know Larry?

What's That Bug? does not endorse extermination