For years, six subspecies of western fence lizard (Sceloporus occidentalis) were recognized, mostly separated geographically. Currently, western fence lizards are being extensively studied. As a result of new DNA work it is expected that the taxonomy of S. occidentalis will be revised to include new species. The former classification with six subspecies will be changed. Before long this northwestern fence lizard (a S. occidentalis subspecies) may have a new scientific designation.
In August I found this northwestern fence lizard (Sceloporus occidentalis occidentalis) outside the visitor center of Lava Beds National Monument in Siskiyou County CA. Western fence lizards are brown, grey or black with lighter blotches. The males have a blue patch on the throat and a blue abdomen, with the blue color absent or very faint in females and juveniles. I was interested in the blue spots on this lizard’s back. These blue spots and the location where this lizard was found led me to conclude it was what is currently known as the northwestern fence lizard subspecies.
Northwestern fence lizards are found north and east of the San Francisco Bay area northward into Oregon and Washington from sea level to 10,800 feet in elevation.
Fence lizards are diurnal and can often be seen basking in the sun on rocks, logs or other surfaces. They are active when temperatures are warm, but become inactive during extreme heat or cold and seek shelter amid rocks, trees, fences – anywhere they can find crevices or burrows.
Also commonly called Pacific fence lizard, the northwestern fence lizard mostly eats insects. When attached its tail detaches easily allowing the lizard to escape its predator.
The genus name, Sceloporus, derives from the Greek “skelos” meaning leg and “porus” meaning “opening” and refers to the pores on the hind leg of a western fence lizard. Occidentalis, the species and subspecies designations, in Latin means “western”, the geographic distribution.
More information on western fence lizards may be found in my previous post on 04-21-12 titled Western Fence Lizard.