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Oakworm caterpillar - Anisota virginiensis

Oakworm caterpillar - Anisota virginiensis
Gainesville, Alachua County, Florida, USA
October 20, 2005
Size: 35 mm
According to Caterpillars of Eastern Forests there are three southern species that look similar. I want to call this Anisota virginiensis, but does anyone know how this is distinguished from A. pellucida, or what the third look-alike is? Found on Parthenocissus quinquefolia, Virginia Creeper, but probably came down from the oak tree above.
CoEF describes the face of A. virginiensis as orange-brown, whereas this one is green - I wonder if that is important?


As BugGuide is now following
the All-Leps classification (discussion here) this specimen is ssp. pellucida that I am calling the Southern Pink-striped Oakworm.

Tony, will you move all
the Florida, Georgia, South Carolina images to pellucida? We can do that if you like. That will leave only the North Carolina images to decide about.

North Carolina images
The best I can do with these is to quote Ferguson (1971) from his MONA Fascicle 20.2A that deals with virginiensis: ". . . thence southward throughout the eastern United States to the Carolinas and the Gulf Staes where, on the coastal plain, possibly from about Cape Hatteras southward, it becomes subspecies pellucida."
Perhaps you or Partrick (if he ever sees this comment) can decide which of the NC images are from the "coastal plain". I have no idea how far inland the coastal plain extends.

We are on the border!
Lynette and I are both "on the border" of the coastal plain. She is (or was) in the Sandhills, a transitional, and unique, area with mostly coastal plain vegetation, but many characteristics of its own. I am in the very lowest Piedmont, just about 20 miles west of the fall line, the boundary with the coastal plain. However I live in the Triassic Basin, a swampy lowland that has much in common, vegetation-wise, with the nearby coastal plain. The vegetation is mostly Piedmont-like, but, for instance, water oak, Quercus nigra is common in bottomlands here--it is usually considered more characteristic of the coastal plain. References I see on Anisota pellucida just say the hostplants are Quercus species--not real helpful.
So, there are no easy answers with this one. Next time I talk to my moth expert friend, I'll ask him about this one.

I just can't get excited about subspecies in this genus--identification of species from photographs is already very iffy. I wrote a lengthy guide page account for the genus with the best reference I could find (1), and I feel one often has to assign photos to species groups--the taxonomy is real unclear. For instance, a common, pesty, oakworm in my area is sometimes listed as A. piegleri, but sometimes as a subspecies or form of A. senatoria:

The photos of cats I have seem intermediate between descriptions of A. peigleri and A. senatoria. I think we finally decided to put them under A. senatoria. It's galling, really, when we have outbreaks and the things cover my windshield in frass, that I can't identify them with certainty! At that point, I just throw up my hands.

Not to crazy about them either
Most species seem to form clines. However I am trying to to follow the All-Leps classification, as this is our taxonomic bible for moths, and it lists 3 ssp. Ferguson in his MONA fascicle treats the 3 subspecies as separate entities and includes a key for their separation but based solely on distribution.
Those of you who don't agree with All-Leps, and favor the Hodges' Check List, should note that Hodges' list recognizes the 3 ssp. This part of the Check List was written by Ferguson but as the primary editor one would assume that Ron Hodges agreed with the classification.
Be nice to see if the genetic gurus at Guelph can find any distinctive DNA between the 3.

I need to take a break
from moving images, so please go ahead and move them.

Anisota virginiensis
Wagner (2005) regards pellucida as a junior synonym of virginiensis, as do Tuskes et al. (1966). Not sure what you mean by the 3rd look-alike, but the only vaguely similar larva is stigma, but I'm sure yours is virginiensis. I doubt that head colour is significant

Thanks, Tony.
I was assuming that there is a third that looks the same based on the remarks in Caterpillars of Eastern Forests (see link above), and I was also assuming that the second look-alike was A. pellucida. Since Wagner is one of the authors of CoEF, I guess A. pellucida was not one of the look-alikes, being merely a synonym. Unfortunately he does not go into details.

I will move to A. virginiensis.

I should have checked
Cats of East For. I just did. I think his 2 similar species are stigma and fuscosa. However, fuscosa is currently considerd a synony of stigma. So there are just 2 similar species: virginiensis and stigma. Larvae of the other 6 Anisota spp. are quite different from these 2.

Thanks, Tony.
I was expecting them to be more similar, but I think it would be hard to get these two confused. Maybe in the earlier instars?
I've added the synonyms to the two guide pages.

Don't know about the pink ones
Patrick Coin has been studying the orange striped ones, see comments at