Experts disagree over whether temnospondyls were ancestral to modern amphibians ( frogs , salamanders , and caecilians ) , or whether the whole group died out without leaving any descendants . Different hypotheses have placed modern amphibians as the descendants of temnospondyls , another group of early tetrapods called lepospondyls , or even as descendants of both groups ( with caecilians evolving from lepospondyls and frogs and salamanders evolving from temnospondyls ) . Recent studies place a family of temnospondyls called the amphibamids as the closest relatives of modern amphibians . Similarities in teeth , skulls , and hearing structures link the two groups .