Do you know what this caterpillar is?
Location: San Diego, CA
May 27, 2011 12:31 pm
We found this caterpillar in San Diego CA at Mission Trails Regional Park on a willow tree. We can not figure out what it is. Can you help. Thanks.
Signature: D in SD
Dear D in SD,
The basic coloration and morphology of your caterpillar and its presence on Willow immediately suggested a Mourning Cloak, known as a Camberwell Beauty across the pond, however, no photos on BugGuide look like this. Mourning Cloak Caterpillars are black spiny creatures (DO NOT TOUCH) and they have 8 rows of orange red dots along the back. Your caterpillar appears to have 9 double rows of orange spines and its variegated pattern is beautiful. We really wish your lateral view was not so blurry. We suspect your caterpillar, whatever it might be, may irritate human skin if in contact with the spines. We did additional research and the Green Comma, Polygonia faunus, also feeds on “willows and birches and others” according to Jeffrey Glassberg’s book Butterflies through Binoculars The West. The photos we found online look even more drastically different than the Mourning Cloak Caterpillar photos posted to BugGuide. Could it be Chlosyne harrisii Harris’s Checkerspot, which we found on the Moth Photographers Group by scrolling down the page. What does Chlosyne harrisii eat? NOPE according to BugGuide, it ranges elsewhere. Here is the Butterflies and Moths of North America website page on the Green Comma.
Alas, our search has turned up nothing conclusive. We strongly believe that the key to a correct identification here is the presence on Willow.
P.S. NEW THOUGHT: Might it be a moth caterpillar like a Buck Moth?
Correction courtesy of Keith Wolfe
“D” and Daniel, this is a Hemileuca (Saturniidae) larva. These nymphalid look-alikes confused me, too, when I first started studying young butterflies.
Funny, Buck Moths did cross my mind when I was researching this caterpillar.
Hi there. Thanks for looking into this for me. After looking Butterflies and Moths of N.A. I do think it is a Nevada Buckmoth.
I really appreciate the time you took to check it out.
D in SD
Bill Oehlke supplies a response
It is definitely Hemileuca nevadensis for first one
and for second one as well.