Temnospondyls are placed as basal tetrapods in phylogenetic analyses , with their exact positioning varying between studies . Depending on the classification of modern amphibians , they are either included in the crown group Tetrapoda or the stem of Tetrapoda . Crown @-@ group tetrapods are descendants of the most recent common ancestor of all living tetrapods and stem tetrapods are forms that are outside the crown group . Modern amphibians have recently been suggested as descendants of temnospondyls , which would place them within crown Tetrapoda . Below is a cladogram from Ruta et al . ( 2003 ) placing Temnospondyli within crown Tetrapoda :