Northern Fence Lizard (Sceloperus undulatus hyacinthinus)
Above and below: This large specimen was photographed sunning itself in a grove of pines in Wicomico County, Maryland (4/10/2005).
Below: A Northern Fence Lizard in Green Ridge SF, Allegany Co., Maryland (4/19/2008). It may be just this individual, but its appearance strikes me as different (including plainer) than fence lizards on the Eastern Shore. And why not? The population in western Maryland has certainly been long isolated from their relatives across the Chesapeake Bay.
The Northern Fence Lizard, one of the Mid-Atlantic's few lizard species, is primarily arboreal in the east. It hunts various invertebrate prey by pouncing on it from a perch.