What is "fence lizard"

n. spiny lizard often seen basking on fences in the United States and northern Mexico

A Fence lizard can be any of several species of spiny lizard (genus Sceloporus), especially:

• The eastern fence lizard or northern fence lizard, Sceloporus undulatus
• The western fence lizard, Sceloporus occidentalis

Note that there are many other species in the Spiny Lizard genus, Sceloporus.