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I've just looked at other images, and some seem lighter green and without the black stripes beneath the pink spots. Is a bit of apparent variability common in these caterpillars? Or is it likely that some of the other images I've seen have been misidentified?
Its all about the stage of maturity of the caterpillar, they begin small and all black, yellow begins to come on them, which becomes green and the black gets less and less. It ends up a big bright green larva with yellow dots and sometimes just the smallest black ring around the yellow wart like spots.
Edit- the spots are sometimes pinkish and I think yours is an example of this. Maybe this changes too? Yellow/pink spots.
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