Did you get it out and count the legs? I think that is possibly a very interesting caterpillar that fell out of a nearby tree. You should rear it to find out what it turns into.
Don, the "haha" was because a. it was more than a week since i had found the creature floating in a bucket of water (probably already dead), and b. I wouldn't know the first thing about trying to rear it. But thank you for your comments and links
Rearing caterpillars is simple: kids do it all the time, see http://lepidoptera.butterflyhouse.com.au/faqs/care.html and is an activity where amateurs can make a difference, really benefiting ecology, as so few larvae are known, and most professional entomologists only work on pest species.
NatureMapr
