meeyauw: Beautiful wood-nymph

Showing posts with label Beautiful wood-nymph. Show all posts

Thursday, August 17, 2023

The Pesky Details

Every photo of mine and Jody's confirmed the misidentification.

Remember these cute August 8 caterpillars when I posted about creatures that camouflage as bird droppings? The first creature I highlighted was the Beautiful Wood-Nymph (Eudryas grata). But it wasn't.

Kathryn got in touch with me last night about a caterpillar she had from her property and could identify to genus but not to species. It was a Eudryas. Without looking closely, I told her it was E. grata, the Beautiful. But she had comparison photos from the Internet and wanted to know how I was sure because she thought it might be a Pearly, E. unio. Now, Kathryn has always had an excellent eye for the small details in insect identification. I remembered how she would keep me honest and see what was in front of us, not what I wanted to see. So I looked up the details.

When I submitted my caterpillar to iNaturalist, the AI said it was E. grata. Jody had named it that, also. And then two other people quickly confirmed it. Without ever looking (but I remember wondering) at the two other Eudryas species caterpillars, I accepted the IDs and moved on. But if Kathryn had doubts, I knew I had to look again.

On Bugguide, there are no photos of the third Eudryas species caterpillar (Eudryas brevipennis), and I could safely ignore that one because it lives west of the Rockies.

There are only two differences between the Beautiful Wood-Nymph caterpillar and the Pearly Wood-Nymph caterpillar: dots on the prolegs (1 dot on the Beautiful and 2 dots on the Pearly on each proleg) and the color of the pro-thoracic shield (orange on the Beautiful and white(ish) on the Pearly), both of which I marked on the photo above. I had to reacquaint myself of the meaning of pro-thoracic and how the heck you find it on a caterpillar, but I did.

Kathryn and I agreed that all the caterpillars that she, Jody, and I had were Pearly and not Beautiful. Which meant I had to update the IDs on iNat, tell Jody, and update my post of August 8.

The moth I posted on August 8 was the Beautiful, and did not belong there with that Pearly caterpillar. Below are my Beautiful moth and Joanne Russo's Pearly moth. The inner brown band is smooth on the Beautiful and scalloped on the Pearly. And that's about it for the difference between the two species. It gets a person to wondering why Nature does this. It must be out of perverse pleasure to making humans nuts.

Beautiful Wood-Nymph - Hodges#9301 (Eudryas grata)

Pearly Wood-Nymph - Hodges#9299 (Eudryas unio)

AND . . . the biggest news!

Kathryn says she is doing bug photos again!

_/\_/\_

Tuesday, August 08, 2023

Beautiful Bird Droppings

Beautiful Wood-Nymph - Hodges#9301 (Eudryas grata)

These caterpillar and moths are prized finds for moth-ers. I have only found one. 😧 They are gorgeous but the prize is that they are one of the creatures that look like bird droppings. You can't tell that from the caterpillar stage; perhaps you can't even tell from the adult moth. But when you see the moth live and in person, they look like bird droppings and you are tempted to move on and search for other insects.

Dorsal view of a Beautiful Wood-Nymph adult on house.

Side view

There are only three species in the genus Eudryas. They all pretty much look the same except for the pattern and shape of the edge of the wings.

The problem with Eudryas (not for me, but for Jody, when she found that caterpillar at her garden) is that they can skeletonize your grape vines. You can see that in the photo below. Jody lets the grapes go in order to let the moths live and because she is not going to use chemicals in her garden. Bugguide says that "[l]arvae feed on leaves of several shrubs, vines: Ampelopsis (a genus of climbing shrubs, in the grape family Vitaceae), Buttonbush, grape, hops, Virginia Creeper. Adults do not feed?" I am very surprised that nobody knows if the adults feed or not.

Our caterpillar devouring Jody's grape vines.

Beautiful wood-nymphs are only one of bird dropping camouflage animals. Another, also difficult to find, is:

Small Bird Dropping Moth - Hodges#9095 (Ponometia erastrioides)

Whenever I see something that looks like bird droppings, I never assume it's a bird dropping. I gently poke with a soft blade of grass to see if it is alive. I'm glad I did that when I found another bird dropping on the bark of a gray birch tree one day and found . . .