Tylosaurus pembinensis

Note: A digitally colored version of the original, available here:
sounder1995.deviantart.com/art…

Tylosaurus pembinensis (Marsh, 1872)

Sauropsida

Diapsida

Lepidosauria

Squamata
Toxicofera

Mosasauroidea

Mosasauridae

Tylosaurinae

Late Cretaceous

Central / Western United States

Length: 15 m

More than a century after Cope and Marsh first dug up fossils of this giant sea lizard, our view of her has changed drastically. We now know that she swam mostly using an asymmetrical tail fluke, was countershaded, and lacked a dorsal crest.

Sunday, September 13th, 2015