The babies only have small yellow spots in contrast to their black body. As they grow bigger, the spots start to change to orange, then red, while white spots form along the entire length of their body. They primarily feed on balsam plants, very rarely would they eat other plants. They have really huge appetite (they can practically finish off the whole plant individually) when close to mature, so I constantly plant more balsams to keep their food source growing. I believe they turn into small orange moths but I’m not entirely sure?
Your caterpillar is a sphinx caterpillar based on the tail. It looks like a white-lined sphinx caterpillar except yours has a black tail and head and the spots are not quite right. You have given a great description of the stages of this caterpillar, but I have not found one to match. Please help provide some more information.
What size are your caterpillars? Where are you located? Is this caterpillar in your garden now – Sept 2010? Do you have a photo of the orange moths? Or a website of what it looks like?
Thanks for the additional input.