Texas alligator lizard
Gerrhonotus liocephalus infernalis

Within the range of this work the alligator lizard is found in Val Verde, Terrell and Brewster counties, into the southern part of the Big Bend.
It is not a commonly seen animal. I have seen them in the rocks in the late afternoon in Palma Draw (Terrell Cty.) and on the road at dusk on hwy. 277, Val Verde County. They attain an adult length of about 20", about 2/3 of which is tail.