Subject: It’s a caterpillar!
Location: Los Angeles
August 14, 2012 6:12 pm
Update–(I wrote last week when it was a baby and I had NO idea what it was. It looked like a legless/tailless lizard)– Now that it’s 2.5+ inches long, I can tell it’s a caterpillar. Two weeks ago it was 1/2 inch long. It hasn’t moved more than a foot! It eats one leaf a night and moves on to the next one. He’s getting awfully big. When you agitate him, two orange spikes? antenna? pop out of the back of his head (2nd photo). I’ve spotted another baby one (3rd photo) – hoping they’re not detrimental to the orange tree. I’ve searched your archives and I can’t find another. Thanks for the help whatsthatbug!
Signature: caterpillar curious!
Dear caterpillar curious,
This caterpillar will eventually metamorphose into a beautiful Giant Swallowtail and the caterpillar is commonly called an Orange Dogbecause it feeds on the leaves of orange and other citrus trees. A few caterpillars will not harm a tree by eating a few leaves. The Orange Dog has two main means of defense. The method you noticed is that when disturbed, it produces a forked orange scent organ known as an osmeterium that releases an odor that some predators find offensive. Also, when resting, the caterpillar resembles a bird dropping rather than the succulent morsel it actually is.