Flora and fauna of the Athens County area, and occasionally habitats outside Ohio. Subject matter will consist of both interpretive material and taxonomic issues in plant and animal identification.

Tuesday, July 19, 2011

Slug Moths of Ohio

That's a caterpillar? Welcome to what I find to be the most interesting moth family of all, the stinging Slug Moths, Limacodidae. Moth caterpillars have a set of prolegs under the body, these have none. Notice the smooth look to the bottom of this larva. Picture yourself with your hands tied behind your back, and you have to move across the floor on your belly. That's kind of how they get around. Because they are slow moving, these caterpillars are equipped with stinging spines. The Saddleback is one most people are familiar with. Hopefully in the future I'll have enough pictures to do a post on just the larvae. This one is Parasa chloris, the Small Green Parasa.

Here is the adult of the caterpillar above. It is one of the more colorful members of the family, and besides, there aren't a lot of green colored moths to begin with.

There are two green members of the family. The other is larger and has more green on the wings. Slug moths often sit with their wings folded down, and their butt sticking up.

Here is one of the VERY small species, Isa textula. The moth is light brown, and the wings have a darker rufus color.

In these photos you can see the other distinguishing marks. Rows of gray crinkly scales that stick up on the wing.

Here is a closeup of the stinging spines of Isa textula. The common name is the Crowned Slug, and you can see it appears to have a crown of thorns all around it.

Lithacodes fasciola, the Yellow-shouldered Slug. Look for the white lightning bolt in the wings for identification.

One of the smallest species in Ohio is the Red-crossed Button Slug, Tortricidia pallida. Look for two thin lines that converge at the top of the wing. Are you starting to see the trend of wings down, butt up?

Looking like a different species, this is actually a dark form of pallida. The thin lines turn into dark blotches.

The most common species in Ohio is the Spiny Oak Slug, Euclea delphinii. The amount of green and orange varies from specimen to specimen. Sometimes they'll have huge green patches covering the wing.

Here is a picture of the Spiny Oak Slug caterpillar. Don't sit on this guy whatever you do! There are 18 species of Slug Moths in Ohio. This was on a Cottonwood, but it was not feeding. They feed on as many as 50 different trees and shrubs. The one plant most of them seek out is Oak. Considering we were in an oak-hickory forest, it's no surprise all of these species were found at the same time. The following are just more examples of their diversity.

Isochaetes beutenmuelleri, the Spun Glass Slug

Apoda biguttata, the Shagreened Slug

Natada nasoni, Nason's Slug

Prolimacodes badia, the Skiff Moth

This is perhaps the worst photo I took all night. I was in an extreme hurry to get this before it flew away. I was very surprised to see it. It's Packardia elegans, the Elegant Tailed Slug. It's known in Ohio from only seven specimens, all but one in northern Ohio. This is only the second time it's been recorded in the southern part of the state. Again, the photo is terrible, but a county record is a county record, and that's what's important.

The Slug Moths are part of the superfamily Zygaenoidea, which includes the Planthopper Parasite Moth, the Smoky Moths, and these guys, Flannel Moths. This is the Yellow Flannel Moth, Megalopyge crispata. Other common names include the Crinkled Flannel or Black-waved Flannel.

Flannel Moths get their name from the rows of raised crinkly scales on the wing that reminded someone of wool. Here's a female above and male below. The markings vary somewhat between sexes, but the antennae are distinctly different.

Here is a picture of the caterpillar. It's sometimes also called the Puss Caterpillar because the soft fur resembles that of a cat.

Make no mistake though, up close you can see under those soft hairs are a series of nasty stinging spines.

I'm not one to get up on a soapbox and boast, not my style. But I would be remiss if I didn't mention that anyone really interested in this group can find my book on the Slug Moths that I wrote with a LOT of help from Eric Metzler and Steven Passoa. It's available from the Ohio Lepidopterists or the Ohio Biological Survey.


  1. What a gorgeous display of Lepidoptera! I'll have to get with you about the location and lighting that enabled you to get such interesting moths! I haven't been at this long, but my city moths are not quite as exciting as your country moths! Love them!

  2. I found a small (just 5/8" long) Spiny Oak Slug Caterpillar near Baltimore, MD this afternoon. Thank you for helping me to identify it!

  3. Just found the green on in new jersey. :)
    Had never seen one before.