How does Gymnophiona fit into the classification of living amphibians?

Gymnophiona (commonly known as caecilians) is one of the three major extant orders within the class Amphibia. Along with the orders Anura (frogs and toads) and Caudata (salamanders and newts), these groups constitute the subclass Lissamphibia.41

Within this classification, the three orders are thought to derive from a single radiation of ancient amphibians and are considered the closest relatives to one another. While they share unique modern amphibian traits—such as pedicellate teeth, moist skin for cutaneous respiration, and a double-channeled hearing system—Gymnophiona is distinguished by its highly specialized, limbless, and wormlike body plan, which is adapted for a fossorial (burrowing) lifestyle.123

Phylogenetically, Gymnophiona is categorized under the subclass Lissamphibia, appearing in the fossil record from the Early Jurassic to the present. Despite their striking differences in structural appearance compared to anurans and caudates, they remain a fundamental component of amphibian diversity.241