This degree of fusion is otherwise only seen in caecilians, amphisbaenians, and uropeltid snakes, all of which are highly specialized burrowers.
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.
Via Caecilia, an ancient highroad of Italy, which diverged from the Via Salaria at the 35th mile (56 km) from Rome, and ran by Amiternum to the Adriatic coast, passing probably by Hadria (Atri).