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Mutant Tomato Worm - Eumorpha achemon

Mutant Tomato Worm - Eumorpha achemon
California, USA
October 9, 2006
I found this caterpillar in the yard today crawling in the grass. I believe it was taken by a bird and dropped so I have no idea what "food" it eats. I have been to several sites about caterpillars and can not identify this one. It is similar in size and shape to a tobacco or tomato horn worm, but is different in several ways:
1) I have never seen one this color
2) Instead of a horn, it has a shiny black, raised dot
3) the "lightening bolt" stripes on the sides go the opposite direction of ALL caterpillars I could find.
4) It has HUGE, well formed, unique droppings.

If you can identify it for me quickly, I can maybe find it's food and keep it alive to moult into a moth. PLEASE HELP!! I live in Sacramento, California, USA.

Images of this individual: tag all
Mutant Tomato Worm - Eumorpha achemon Mutant Tomato Worm - Eumorpha achemon Mutant Tomato Worm - Eumorpha achemon

Well, at least we agreed with Hannah on the genus!
Check out her article on raising caterpillars here

Some similar images
can be found under Eumorpha fasciata, the Banded Sphinx, which is very variable and has the stripes going the wrong way as yours do. Didn't see an image here with a button, but it clearly loses its horn. Feeds on the Evening Primroses, Onagraceae, but from the size, this one may just be looking for a place to pupate and wait out the winter.

Achemon sphinx, I believe
those segmented spiracular spots and the lack of a horn in later instars are typical. See guide and compare below:

If it was wandering, it's likely preparing to pupate and you needn't feed it anything. It needs to burrow into the ground or at least some kind of soil substitute, though

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