prairiecommunity: Gaillardia World: Moth Caterpillars (Including Con Artists)

A "Camouflaged Looper." Can you tell what's flower and
what's bug?

Camouflaged Loopers are ingenious caterpillars that lived on Gaillardia pulchella all summer long. They are the larvae of the Wavy-Lined Emerald Moth, Synchlora aerata,

I first noticed these caterpillars while watching some beetles. Suddenly, I was distracted by the disk flowers rising up and waving around. I watched, astonished, as the flowers moved across the disk. Birnam Wood was going to Dunsinane! But unlike MacBeth, I looked more closely and saw that some nebulous creature, her outlines hidden under pasted-on flower-parts, was the prime mover. Other Gaillardia plants also boasted such costumed beings! A few Google searches later, I learned their identity--Camouflaged Loopers.

Indeed, they are masters of disguise.

While some insects have evolved to resemble their host plants, Camouflaged Loopers have a more flexible strategy to hide from predators. They choose a plant to feed on and then adorn themselves with parts of that plant in order to blend in with those particular flowers. Thus, they can feed right out in the open, hopefully unnoticed.

Unless they move, they look just like a bit of flower detritus:

Here they are in action:

How do they create their costumes? Mineralized "spikes" grow along their backs, sort of like horses' teeth or our own fingernails. The Loopers chew flower parts and inject them with a glue-like liquid from a special gland. Then they fasten the sticky mass to the spikes. And there they are--all dolled up!

The caterpillars were in no hurry to metamorphose. We had them with us from the heat of June to the freezes of October. Camouflaged Loopers overwinter in the ground and don't metamorphose to moths until warm weather returns. So as frost killed the flowers, these little guys went down into the soil to await further transformation in the spring.

Synchlora aerata is part of a moth family called Geometridae, Greek for "Earth Measurers." Following this theme, the caterpillars are called "Inchworms," "Measuringworms" or "Spanworms." They are also called "Loopers" because of their anatomy and peculiar locomotion. Loopers have legs on their thorax, but no legs on the abdomen--just two pairs of prolegs at the rear. To move, they raise up their legless middle to form a U and then bring their hind end up to meet the thorax. Once the "loop" is formed, the front end stretches out into new territory, measuring the earth by "inching" forward.

Here are some more Loopers from the family Geometridae, difficult to identify further, as the caterpillars of numerous species resemble each other. The green ones were especially common on Gaillardia, throughout the summer.