Corn snake
The corn snake is named for the species' regular presence near grain stores, where it preys on mice and rats that eat harvested corn. The Oxford English Dictionary cites this usage as far back as 1675. Some sources maintain that the corn snake is so-named because the distinctive, nearly-checkered pattern of the snake's belly scales resembles the kernels of variegated corn. Regardless of the name's origin, the corn reference can be a useful mnemonic for identifying them. Their diet in the wild mainly consists of rodents, small amphibians, birds and/or their eggs, other types of eggs, and so on. They're not known for eating insects, though. In captivity they're usually fed a steady diet of pinky mice and other types of creatures such as the ones above.