Dub and Halfbreed both have good plans! Lol
A "Black Racer" as most country folk call them, is an Indigo King Snake. Fairly common in Texas and the southern states. They get big, 5-7 feet. Would be perfect.
Ok....I checked myself....not true....two different snakes. Anyway...you can find the Indigo King in Texas but any type of king snake would work. As far as "Racers" I can't say for certain they eat other snakes.