 The <unk> family <unk> is thought to be most closely related to Lissamphibia . In 2008 , an <unk> called <unk> <unk> was named from Texas and was nicknamed the " <unk> " for its frog @-@ like head and salamander @-@ like body . It was thought to be the most closely related temnospondyl to lissamphibians and was placed as the sister taxon of the group in a phylogenetic analysis . Another species of <unk> called <unk> annectens is now thought to be even more closely related to lissamphibians . Unlike <unk> , <unk> was known since 1969 , and the presence of pedicellate teeth in its jaws has led some paleontologists to conclude soon after its naming that it was a relative of modern amphibians . It was first described as a " <unk> " , and the specific name annectens means " connecting " in reference to its inferred transitional position between <unk> and lissamphibians . The structure of its tympanum , a disk @-@ like membrane that functions like an ear drum , is similar to that of frogs and has also been used as evidence for a close relationship . Other features including the shape of the palate and the back of the skull , the short ribs , and the smooth skull surface also point to it being a closer relative of lissamphibians than is <unk> . Below is a cladogram modified from <unk> and Bolt ( 2010 ) showing the relationships of <unk> , <unk> , and Lissamphibia : 
