Gymnophiona (order)

Order of serpent-like amphibians, having a compact skull for burrowing with many compound bones, limbs or girdles, a persistent notochord, typically having naked skin (although some have scales), complete metamorphosis like frogs and toads, a compact skull, and lidless tiny eyes nearly hidden by the skin. Dates from Early Jurassic to present, with six extant families and about 170 living species.