Mahar

Hollow Earth Fauna: The Mahars - the once dominant race of the Hollow Earth world of Pellucidar, created by Edgar Rice Burroughs. 

"A more hideous thing it would be impossible to imagine. The all-powerful Mahars of Pellucidar are great reptiles, some six or eight feet in length, with long narrow heads and great round eyes. Their beak-like mouths are lined with sharp, white fangs, and the backs of their huge, lizard bodies are serrated into bony ridges from their necks to the end of their long tails. Their feet are equipped with three webbed toes, while from the fore feet membranous wings, which are attached to their bodies just in front of the hind legs, protrude at an angle of 45 degrees toward the rear, ending in sharp points several feet above their bodies."

"A rhamphorhynchus of the Middle Olitic, David," he said, "but, gad, how enormous! The largest remains we ever have discovered have never indicated a size greater than that attained by an ordinary crow."