It has long been thought that lizards evolved from a group of amphibians called anthracosaurs, no fossils of which have been found in any rocks older than 300 million years  However, a fossil of a lizard was recently found that is estimated to be 340 million years old  Lizards could not have evolved from creatures that did not exist until after the first lizards
Ttherefore, lizards could not have evolved from anthracosaurs
unknown lizard fossils older than 340 million years