Western fence lizards (Sceloporus occidentalis) are sturdy reptiles that predominantly reside in California, although they also occasionally inhabit nearby states -- think Nevada, Oregon and others. These diurnal lizards are members of the family Phrynosomatidae. Since western fence lizards are sexually dimorphic creatures, telling the males and females apart usually isn't too difficult.
Western fence lizards are of moderate size. When fully mature, they can grow to anywhere between 2.2 and 3.4 inches in length. Their bodies are either blackish-brown, brown or gray in coloring, with much paler undersides -- usually yellow or white. Their legs and upper portions are adorned in prickly scales that are either brown, beige or gray. Western fence lizards usually live in forests, grassy plains, rugged canyons and environments with plentiful sagebrush. They're occasionally spotted in agricultural areas, as well. Insects such as ants and beetles are major food staples for these reptiles. They also sometimes dine on arthropods.
One of the quickest and simplest ways to tell male and female western fence lizards apart is by looking at their throats and stomachs. Male specimens feature bright blue markings on their throats and on the edges of their stomachs -- a feature the females usually lack although, when they do have it, it's usually a lot subtler and harder to detect. Western fence lizards are frequently called "blue bellies" -- a nod to this striking coloration. Boy western fence lizards also sometimes have random green or blue blots over their scales.
Their blue bellies aren't the only way to distinguish between male and female western fence lizards according to color. The female's overall body coloring is generally paler than that of males. Youngsters are also typically paler than adult male specimens. The tops of western fence lizards' bodies are often covered in dark spots but, since the females aren't as dark as the males, their spots usually are significantly easier to discern.
Outside of the color realm, male and female western fence lizards' tail areas don't look exactly the same. The foundations of the males' tails tend to be a lot wider and more "bloated" in appearance than those of the females. The males also feature sizable scales in back of their vents.
- Washington State Department of Natural Resources: Western Fence Lizard
- Burke Museum: Western Fence Lizard
- United States Geological Survey Western Ecological Research Center: Western Fence Lizard
- Northern Rockies Natural History Guide: Western Fence Lizard
- USA National Phenology Network: Sceloporus occidentalis
- Digital Atlas of Idaho: Sceloporus occidentalis