Speedy Rustling

The speedy rustling split from its ancestor, the ringed rusting. Sometimes it happened that the ringed rusting had to travel a long ways to reach food, so to compensate, they got much smaller. This smaller size means it doesn't have to eat as much, while the smaller size means it can go farther, faster. The reason for the increase in speed is because while the shell has shrunk, the leg muscles have not. Other than these changes, it is the same as before.