Prosalirus bitis is the name given to a fossil frog found in Arizona in 1981 by Farish Jenkins, which has primitive features, but has mostly lost the salamander-like traits of its ancestors.
Vertebrates present here at the time of Oligokyphus included hybodont sharks, bony fish known as osteichthyes, lungfish, salamanders, the frog Prosalirus, the caecilian Eocaecilia, the turtle Kayentachelys, a sphenodontian reptile, various lizards.