Entomology (Study of Bugs)/Mystery Caterpillar


Mystery Caterpillar
Mystery Caterpillar  
My son and I found this caterpillar on a nature hike at the Bolsa Chica wetlands in Southern California. I've tried to look it up to see what it is but haven't had much success.

It is larger (maybe 1.5"), black hair all over it.  On it's belly and lower sides is yellow spots and tufts on hair as well.  

Can you tell me what kind of caterpillar this is and what it will turn into?

Dear Toni - This appears to be a salt marsh caterpillar, Estigmene acrea (Lepidoptera: Erebidae; subfamily Arctiinae) - see http://tinyurl.com/a6c4ho4 for an example that also includes an image of an adult moth. This is a very common and widespread species, but the caterpillars are so variable in color pattern that one might not think that they all are the same species!

Hope this helps,

Entomology (Study of Bugs)

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Ed Saugstad


Will accept most questions in general entomology, including those related to medical entomology, taxonomy, ecology, arthropod surveillance, and pest management. If you are requesting a 'mystery bug' identification, PLEASE either attach an image to your question, or post an image on a web page (such as Flickr) so that I can look at it, as verbal descriptions frequently are insufficient for a definitive identification.


21 years in the U.S. Army as a medical entomologist; duties varied from surveillance of pest populations (including mosquitoes, cockroaches, ticks, and stored products pests) to conducting research on mosquito-virus ecological relationships and mosquito faunal studies. Ten years as a civilian analyst for the Department of Defense, primarily on distribution of vector-borne diseases worldwide. Limited experience on surveillance of agricultural insects in North Dakota and Indiana.

Entomological Society of America, West Virginia Entomological Society, Society for Vector Ecology, National Speleological Society, West Virginia Association for Cave Studies.

American Journal of Public Health, Contributions of the American Entomological Institute, Japanese Journal of Sanitary Zoology, Journal of Economic Entomology, Mosquito News, and Mosquito Systematics.

B.S. in entomology from North Dakota State University in 1963, M.S. in entomology from Purdue University in 1967.

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