Subject: Big caterpillar
Location: Austin, TX
July 24, 2012 11:22 pm
Hi Daniel, I found this caterpillar on oxypetalum, a milkweed relative. It’s about 2.5 – 3” long. Sorry the pictures aren’t great. The caterpillar has white knobs on it head. Thanks.
This is sure a distinctive caterpillar. Thank you for supplying a food plant name as that usually makes identification much easier. We started with a web search of caterpillar and Oxypetalum and we found a photo of several Monarch Caterpillars and a mention that they can feed on Oxypetalum caeruleum. We then learned that the plant is also called Tweedia or Blue Flowered Vine on Forest Farm and Dave’s Garden has a comment that Monarch Caterpillars will feed on it. We couldn’t find anything online that resembled your caterpillar by searching the food plant, but we did learn quite a bit about the plant including that it is from South America. Other than to say we believe this is most likely a moth caterpillar and it reminds us of the Prominent Moth Caterpillars in the family Notodontidae which is well represented on BugGuide, especially the subfamily Heterocampinae, we are quite clueless. Perhaps one of our readers will be able to assist in this identification.
A friend has identified it for me. It is a Lassaux’s Sphinx (Erinnyis lassauxii) caterpillar. I thought it might be a type of Prominent Moth, too; but it is in the Sphingidae family. Thank you for help, though. I enjoy your website.
Thanks so much for writing back to us with the identification. We would never have thought of a Sphinx Moth because of the lack of a caudal horn. The photos on the Sphingidae of the Americas website are an exact match.