Currently viewing the category: "Inchworms"

Subject:  What is this caterpillar?
Geographic location of the bug:  Sydney, Australia
Date: 03/20/2021
Time: 02:49 AM EDT
Your letter to the bugman:  Hi
Found this little agile one eating my curry leaves. Want to know if it is a pest amd curious about it’s species. Thank you.
How you want your letter signed:  Curious gardener

Inchworm on Curry Plant

Dear Curious Gardener,
This is an Inchworm or Spanworm in the family Geometridae.  We believe it might be
Hyposidra talaca based on an image posted to the Butterfly House website.  Though curry is not listed as a food plant, the site indicates:  “It is polyphagous, eating the foliage of many plants including the crops.”

Thank you so much for the information.

Subject:  Caterpillar
Geographic location of the bug:  Denton, Texas
Date: 05/02/2019
Time: 12:05 AM EDT
Your letter to the bugman:  This caterpillar is very thin, about 1 inch long. I found it on some Mystic Spires salvia. I would like to know what it will turn into.
How you want your letter signed:  M. Hector

Possibly Pink Inchworm

Dear M. Hector,
This is an Inchworm or Spanworm in the family Geometridae.  We have received images of pink Inchworms in the past, and we have not been able to provide more than a family identification, including this pink Inchworm from Minnesota in 2009.  We also located an image of a pink Inchworm on BugGuide that is only identified to the family level.  So, the best we can do is provide a family identification at this time.  Moths from the family Geometridae often have a very distinct shape including wings with scalloped edges.  Though it does not answer your question, you might be amused by this 2012 request to identify a pink Inchworm that garnered a Nasty Reader Award.

Unknown Pink Caterpillar on Salvia

Upon further scrutinizing your other images, we cannot even be certain that this is an Inchworm in the family Geometridae.  Do you by chance have a lateral view that shows the legs?

Subject:  Stickbug?
Geographic location of the bug:  Silver Spring, MD
Date: 08/12/2018
Time: 12:14 PM EDT
Your letter to the bugman:  Found this in the back yard.  Looks like there maybe eggs on its back.  Is it going to mess up my garden?
How you want your letter signed:  Gene

Parasitized Inchworm with Chalcid Pupae

Dear Gene,
Your “stickbug” is an Inchworm or Spanworm, the caterpillar of a moth in the family Geometridae, and they are excellent twig mimics.  What you have mistaken for eggs are actually the pupae of parasitoid Chalcid Wasps.  Here is a similarly parasitized Inchworm on BugGuide and here is an image of the Chalcid Wasp that emerged, also on BugGuide.

Subject:  Moth with eggs
Geographic location of the bug:  Mississippi
Date: 08/02/2018
Time: 04:46 PM EDT
Your letter to the bugman:  This moth laid it’s eggs on the wall right next to my front door, so it was hard to miss. It looks a bit like the Early Thorn moth, but as far as I can tell from my google searches, they are not supposed to be in North America, so I must be mistaken. However, I can’t find a picture of any other moth that is similar so I thought I’d write to you. I have a young child and thought we might have fun keeping track of the eggs as long as the caterpillars that emerge aren’t the kind that sting. If they are I’ll know to be more cautious.
How you want your letter signed:  Thanks for all you do,

Curve-Toothed Geometer with Eggs

You are most welcome.  We quickly identified this Curve-Toothed Geometer, Eutrapela clemataria, on the Insect Identification site where it states:  “The only moth in its genus, the Curve-Toothed Geometer Moth has many distinctive markings that should help in identifying it. When at rest with wings flat, a definitive line that crosses from left to right stops short of reaching the edges of the wings. This line separates dark brown coloring near the head from the lighter brown color at the edge of the wings. The outer edge of the forewings curves downward and ends in a nubby point, or tooth, at the tips of the wings. The hindwings have scalloped edges.  A young caterpillar has a brown body that becomes darker and more purple as it ages. It eats the leaves of common trees like ash, oak, and maple. This easily accessible food source makes it almost effortless when expanding its range. Two generations are produced each year in warmer climates. Adults are active from late spring to late summer in wooded areas across the continent.”  The green eggs are very distinctive, so we attempted to look for images of eggs, and we found the same images of the green eggs on both BugGuide and The Moth Photographers Group.  To the best of our knowledge, no Geometer caterpillars, known as Inchworms or Spanworms because of their manner of locomotion, pose a danger to humans.  If you decide to try to raise some caterpillars, we would urge you to transfer the majority of the hatchlings to one of the mentioned host trees and try raising about 20 or so in captivity.

Subject: Camouflage Looper?
Location: Tulsa, Oklahoma
August 25, 2016 10:43 pm
Hi — Love your site — thanks for all your work. I found this little guy while I was taking photos at a pond near Tulsa, OK, a few weeks ago. At first I couldn’t figure out what it was because it was in the pink tufts of the flower. But then, I used a blade of grass to coax it out on to a leaf. Once it stretched out, I could see it was an inchworm. I’d never seen one like this before!!
Do you know if the “camouflage” bits get stuck on passively as the inchworm crawls around, or does the worm actively attach them?
Signature: Terrie

Camouflaged Looper

Camouflaged Looper

Dear Terrie,
Thanks for the compliment and thanks for sending in your awesome images of a Camouflaged Looper,
Synchlora aerata, or another member of the genus.  According to BugGuide:  “Caterpillar adorns its body with plant fragments, usually flower petals, to camouflage it as it feeds. It is the only widespread species to do so(2), but from Maryland southwards other Synchlora spp. are also present and only raising to adulthood can yield a definite caterpillar ID.”  We suspect the caterpillar uses silk to attach the flower bits to its body.

Camouflaged Looper

Camouflaged Looper

Subject: Help Identify
Location: Talbott, Tn 37877 in a 80 year old cedar tree
July 20, 2016 5:04 pm
My daughter recently found this little guy hanging from what appeared to be a spider web but upon further examination could have been its own silk. I have been told that it could be a chameleon worm but I can’t find any info to back it up. Can you help identify please? I would like to know incase my daughter finds another one I can tell her to either stay away or its safe to touch. Thanks in advance!
Bryan Hux
6th Grade Science
Jefferson Middle School
Jefferson City Tn
Signature: Bryan Hux

Unknown Spanworm

Juniper Twig Geometer

Dear Bryan,
Though we have not had any success with a species identification, we can tell you this is an Inchworm or Spanworm in the family Geometridae, and it poses no threat to humans as it is neither venomous nor poisonous.  We wish we could be certain that the cedar upon which it was found was also the host plant as we couldn’t find any similar looking Spanworms associated with cedar.  Perhaps one of our readers will have more success at a species identification than we have had searching BugGuide and other sites. 

Karl finds the ID
Hi Daniel and Bryan:
It looks like a Juniper-twig Geometer caterpillar (Patalene olyzonaria). Despite the name, the principal food for the caterpillars is given as cedars of all varieties. Regards, Karl

Thanks so much Karl.  We like our name “Diamondback Spanworm” since the BugGuide description is:  “Larva: body brownish or grayish with dark angular lines dorsally and laterally, creating a diamond-shaped pattern; whitish patches below angular lines in subdorsal area; pair of black dorsal warts on ninth abdominal segment; head brown and gray with dark brown herringbone pattern on lobes.”