Answer:
Judging by what I know, it could be around 350 million to 400 million years old. The horseshoe crab, the American cockroach, coelacanth, and frilled shark are all 350 million to 400million years old. In wikipedia, it said the komodo dragon ate the stegodon, but right now, we need to find out how long ago the stegodon lived. I am guessing it is, as I said, 350 million to 400 million years old.