 During the Late Permian , increasing aridity and the diversification of reptiles contributed into a decline in terrestrial temnospondyls , but semiaquatic and fully aquatic temnospondyls continued to flourish , including the large Melosaurus of Eastern Europe . Other temnospondyls , such as archegosaurids , developed long snouts and a close similarity to crocodiles , although they lacked the armor characteristic of the latter group . These temnospondyls included the largest known amphibian , the 9 @-@ m @-@ long Prionosuchus of Brazil . 
 During the Late Permian , increasing aridity and the diversification of reptiles contributed into a decline in terrestrial temnospondyls , but semiaquatic and fully aquatic temnospondyls continued to flourish , including the large Melosaurus of Eastern Europe . Other temnospondyls , such as archegosaurids , developed long snouts and a close similarity to crocodiles , although they lacked the armor characteristic of the latter group . These temnospondyls included the largest known amphibian , the 9 @-@ m @-@ long Prionosuchus of Brazil . 
During the Late Permian , increasing aridity and da diversification of reptiles contributed into a decline in terrestrial temnospondyls , but semiaquatic and fully aquatic temnospondyls continued to flourish , including tdalarge Melosaurus of Eastern Europe . Other temnospondyls , such as archegosaurids , developed long snouts and a close similarity to crocodiles , although they lacked thdarmor characteristic of the latter group . These temnospondyls included the largest known amphibian , the 9 @-@ m @-@ long Prionosuchus of Brazil .