8 Caterpillars and Inchworms from April 11-17 2021

These eight critters that I imaged in the neighborhood between April 11 and 17 had fascinated me but also mystified me. Inchworms are a subset of caterpillars. Seems that the locomotion means indicates which animal is which. Viewing video movement is a lot more helpful than viewing still captures. I looked up anatomy and diagrams, then viewed videos that contrast inchworms and caterpillars.

Overall Contrasts Between Inchworm and Caterpillar

"Inchworms" explains the familial relationship and big-picture contrasts.

The common name "inchworm" applies to a large group of caterpillars that includes many different species of moth larvae. ... In different regions throughout the United States, the common name inchworm may apply to native and non-native leaf-feeding caterpillars also known as spanworms, cankerworms, loopers, moth worms and measuring worms.

Common caterpillars have a series of true legs and fleshy "prolegs" that support movement from head to tail. In contrast, inchworms have true legs at the front and prolegs at the rear with a legless expanse in between. To travel forward, inchworms take it one end at a time, as though they're measuring their route. First, the rear moves forward, causing the legless midsection to arch or "loop" up. Then the inchworm lifts and extends its front end, and the rear begins to move again.

"Inchworm Identification" explains:

They're the larval stage of moths of the Geometridae family. ... The easiest way to identify inchworms is by their movement. Inchworms, also called cankerworms, bend their smooth bodies upward in the middle, bringing their hind prolegs up to meet their front true legs -- the legs that will remain in adult moth form -- then pushing their front legs forward to extend their bodies again. It looks almost as if the worms are measuring the tree branch as they walk.

• "Insect Anatomy: The Parts of a Caterpillar" and "Caterpillar Anatomy" each provides a good image that identifies caterpillar parts, followed by descriptions.
• One Google results page shows several diagrams of inchworms, although descriptions are not as easy to find.
• "How Caterpillars Crawl - Extreme Close Up" interestingly lives up to the video title.
• "Inchworms" shows several inchworms inching along for entertainment and amusement.
• "Caterpillars Dancing how they move crawl insect macro video" focus qualities are somewhat inconsistent, but close-in views contrast caterpillars from inchworms.

Mysterious Matchhead-esque Caterpillar/Inchworm

I recorded the half-inch critter April 11 and uploaded it to YouTube https://www.youtube.com/watch?v=B5_wI76Za4E, requesting some ID help. I received suggestions that don't seem to have panned out (Indian moth larva, fungus gnats). Looking online yielded close-but-no-cigars images. I did run across other prospective topic critters, such sawflies, maggots, and grubs. "What Are the 5 Types of Insect Larvae?" provides a good overview of wormy larvae types. For that matter, the Scarabaeiform ("grub") bore a head and body color/shape resemblance, but the rest of the description, nah.

Two Days, Two Inchworms

I recorded one on April 13, and the next one on April 14. No doubt, with their moving forms and also distinctive hind areas that resemble miniature hippo bodies and chunky, trunky legs.

Trapeezy Caterpillar, I Presume

Another April 14 capture, the critter was in suspension and view. The slowed-down clip seems to show glimpses of legs on the entire body length, so I concluded it was a caterpillar. I still waffle over whether I saw caterpillar legs or not. A video that accompanies mid-April "Central Texas caterpillars are out, but only some could potentially destroy your garden" shows a trapezey critter that definitely is an inchworm. OTOH, Google images and Shutterstock [] show trapezey critters that could be non-inchworm caterpillars.

Disheveled-looking Critter

It was not my most elegant capture (April 14), but interesting enough for me to attempt to ID it. The closest critters I thought it might be were "asp caterpillar" or "puss caterpillar", hairy like toupees, and dangerous to touch.

Little Critter with Bulbous Head and Hindsection

This final capture for April 14 was about the length of a pinky fingernail. It wasn't much of a mover, but just enough undulation to indicate it was a caterpillar.

Spasticky Caterpillar

This critter bounced around, then went on the straight and narrow, along a length of grout. I was able to view enough legs and motion to conclude it was a caterpillar, not inchworm.

Jadelike Caterpillar with Measuring Stick

This caterpillar was the critter I was most prepared to capture. After I placed a 4-inch ruler near it, it edged closer so I could record it in real time for distance. The color reminds me of light green jade.

Additional Meandering Buggy Resources

• "Learn about Texas Insects"
• "Caterpillar Facts & Worksheets"
• "Guide: Find Your Caterpillar With Photos and Descriptions"
• "How Does a Caterpillar Turn into a Butterfly?"
• "PHOTOGRAPHS OF THE SPECIES:SKIPPERS, BUTTERFLIES & MOTHS"
• "Inchworm Life Cycle" (excellent closeup of inchworm)
• "Infestation of Inchworms"
• "Oak Leaf Roller and Springtime Defoliation of Live Oak Trees"

Additional Meandering Resources Pertaining to the Matchhead-esque Critter

• Google results for "white worms with red heads" (attempt to ID the matchhead-esque critter)
• "Differences Between a Caterpillar & a Grub"
• "The Similarities Between Maggots & Caterpillars"
• "Identifying soil beetle pests"
• "Is it a Sawfly Larva or a Caterpillar?"
• "What Are Sawflies?"
• "Pantry Pests - Indianmeal Moths in Food" (at 1:43, large image)
• "Indian meal moth caterpillars feeding" provides a very close look, especially starting around 43-sec mark. Lack of dark markings indicate these caterpillars are not the matchhead-esque critter.
• "How To Get Rid Of Fungus Gnats ( Send'em To The Shadow Realm )" at the 39-sec mark, the worm looks transparent. Also good views starting about 3 1/2 minutes. Good info about gnat control.
• "Crap!! I think I might have Fungus Gnat Larvae"

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Related:

• "Leggy Bugs—Caterpillars (Lepidopteran Larvae, which Become Butterflies and Moths)"
• "Leggy Bugs--Inchworms"

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