Buffalograss

A Texas native turfgrass with much lower water needs than commonly used turfgrasses (bermuda, zoysia, St. Augustine).
Texas Parks & Wildlife: Buffalograss

Only three North American grasses are both drought tolerant and suitable for use as a lawn. Of these, only buffalograss is commonly available and so it has become quite popular since the 1980s. Though the other two, blue grama and curly mesquite grass (Hilaria belangeri) are occasionally used.
-- Wikipedia: Bouteloua dactyloides