Cryptolacerta hassiaca: A New Basal Amphisbaenian

The recent discovery by researchers from the University of Toronto Mississauga and the Museum für Naturkunde Berlin, Germany of a tiny, 47 million-year-old fossil of a lizard called Cryptolacerta hassiaca provides the first anatomical evidence that the body shapes of snakes and limbless lizards evolved independently.

"This fossil refutes the theory that snakes and other burrowing reptiles share a common ancestry and reveals that their body shapes evolved independently," says lead author Professor Johannes Müller of Humboldt-Universität, Berlin.

The fossil reveals that amphisbaenians are not closely related to snakes, but instead are related to lacertids, a group of limbed lizards from Europe, Africa and Asia. "This is the sort of study that shows the unique contributions of fossils in understanding evolutionary relationships," says Professor Robert Reisz from the University of Toronto Mississauga, the senior author of the study. "It is particularly exciting to see that tiny fossil skeletons can answer some really important questions in vertebrate evolution".

The German research team, led by Müller and American graduate student Christy Hipsley, used X-ray computed tomography to reveal the detailed anatomy of the lizard's skull and combined the anatomy of Cryptolacerta and other lizards with DNA from living lizards and snakes to analyze relationships. Their results showed that Cryptolacerta shared a thickened, reinforced skull with worm lizards and that both were most closely related to lacertids, while snakes were related to monitor lizards like the living Komodo dragons.

The press release was badly written, IMNSHO.