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, and related families

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. This one is Parasa chloris, the Small Green Parasa. If you would like to see a post on more of the caterpillars, click here

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.

The Large Parasa or Stinging Rose Caterpillar, Parasa indetemina. A slightly bigger species than the above, and with a broader green patch on the wing. The hind wings are lighter colored when compared to chloris. Diane Brooks photo.

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.

D. Brooks photo

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

Early Button Slug, Tortricidia testacea.  D. Brooks

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. At one time these were split into two species, the other being T. flexuosa. They are virtually identical, and can not even be separated by genitalia, so they are currently combined as pallida.

Jeweled SlugPackardia geminata.

D. Brooks photos. As I mentioned with the previous species, the brown moth was once separated as a different species P. albipunctata, but is now simply considered a dark form of geminata.

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! It's a real whoopee-cushion. 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 most of these species were found at the same time. The following are just more examples of their diversity.

Isochaetes beutenmuelleri, the Spun Glass Slug
D. Brooks

Apoda biguttata, the Shagreened Slug

Natada nasoni, Nason's Slug

Yellow-collared Slug, Apoda y-inversum. D. Brooks

Prolimacodes badia, the Skiff Moth

Adoneta bicaudata, Crested Slug

D. Brooks

Purple-crested Slug, Adoneta spinuloides. This has the same black and white markings as the Crested Slug above, but the wing is straw colored on that species. The Purple-crested is a chocolate brown, and more commonly encountered. D. Brooks photo

The Saddleback, Acharia stimulea

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.

Here's a much better updated pic from Diane.

Hag Moth, Phobetron pithecium. D. Brooks photos

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.

White Flannel Moth, Norape ovina.

Orange-patched Smoky Moth, Pyromorpha dimidiata. This is one of three Smoky Moths in Ohio, all of which can be found flying during the day. The wings on this species are half black and half yellow-orange.

Grapeleaf Skeletonizer. Harrisina americana. Similar to the Yellow-collared Scape Moth (Cisseps fulvicollis), this species has a brighter orange collar, a black body, and large tufts of hair at the end of the abdomen. They often hold their wings open like this when at rest. Larvae feed in groups, eating the soft tissue of grape, and leaving the main veins behind.

Our smallest species could be mistaken for a Net-winged Beetle. It's Clemens' Smoky Moth, Acoloithus falsarius. It lacks the hair tufts on the abdomen tip. The orange collar does not completely cover the neck. It is broken in the middle by black. This species keeps its wings folded roof like over the back.

Planthopper Parasite Moth, Fulgoraecia exigua. This is the sole member in Ohio of a family whose larvae feed externally on the body fluids of Homopteran plant-hoppers. Most of the specimens will show a small pale circle in the wing. This helps to separate them from the similar looking black Bagworm moths.

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.

  4. I found one about 25 minutes ago, it dose not look like any of the ones you have posted up here, I am in Reynoldsburg Ohio, and I found it by a slow running stream. I did take several pictures of it. And I touched like a dummy and got stung,lol.

  5. I have one I'd love to have identified. Would you like my photos?

  6. I found one in buffalo ny and didnt know what it was picked it up to put outside thinking it was an ordinary moth but it left a nasty sticky fluid on my finger. It was a saddleback ..is it posionous?