A basilaris complex is absent from the inner ear. The recessus amphibiorum is oriented vertically in the inner ear. The otic sac is bulbar and unvascularized. The amphibian periotic canal lacks fibrous connective tissue. The periotic cistern is large and does not protrude into the fenestra.
Lungs are present but the ypsiloid cartilage is absent.
Two pairs of gill slits are present. The scapula and coracoid bones of the pectoral girdle are fused to form the scapulocoracoid. Vertebral centra are amphicoelous. Ribs are bicapitate. Spinal-nerve foramina are absent from all vertebrae.