Urosaurus nigricauda Black-tailed Brush Lizard
Also known as:
Small-scaled Lizard
Once upon a time these lizards from extreme southern California were considered Urosaurus microscutatus . Later, U. microscutatus was lumped with U. nigricaudus, and these lizards were therefore considered the latter species. In 2015 Andrew David Gottscho's Ph.D. thesis brought back the name Urosaurus microscutatus for these. But it doesn't seem to have stuck; the Reptile Database and other online taxonomies are still using nigricaudus, though now gender-corrected to nigricauda.
Borrego Palm Canyon, Anza-Borrego Desert State Park, San Diego County, CaliforniaAugust 1, 1999
Black-tailed Brush Lizard (Urosaurus nigricauda)
This small lizard was a brave little showoff, flashing his belly colors, doing pushups, waggling his tail, and chasing off all nearby lizards, including much larger banded rock lizards and granite spiny lizards. Stebbins mentions Borrego Palm Canyon as the northernmost tip of the range of this species.
Borrego Palm Canyon, Anza-Borrego Desert State Park, San Diego County, CaliforniaJuly 2, 2006
Black-tailed Brush Lizard (Urosaurus nigricauda) Black-tailed Brush Lizard (Urosaurus nigricauda)
I was back at the same beautiful desert canyon seven years later on a blisteringly hot day. It was so hot that there were very few reptiles out, just a handful of side-blotched lizards and whiptails. When I reached the highest point I was intending to reach, I sat down on a boulder in the shade to rest for awhile and kill some time before heading back down the canyon. (I wanted to kill some time to avoid disturbing a small herd of desert bighorn sheep that were browsing and drinking in the part of the canyon I had climbed up through earlier.)

While waiting, I caught sight of this little guy on a nearby boulder. I spent fifteen minutes watching it dash from one rock to another, gobbling up a number of tiny insects.

Borrego Palm Canyon, Anza-Borrego Desert State Park, San Diego County, CaliforniaApril 27, 2009
Black-tailed Brush Lizard (Urosaurus nigricauda)
Maybe one of these years I'll see a Urosaurus nigricauda somewhere other than Borrego Palm Canyon. But maybe not.
Meling Ranch, Baja California, MexicoMay 15, 2013
Black-tailed Brush Lizard (Urosaurus nigricauda) Black-tailed Brush Lizard (Urosaurus nigricauda) Black-tailed Brush Lizard (Urosaurus nigricauda)
Hey, this isn't Borrego Palm Canyon! Meling Ranch is a convenient place to stay if you're heading into Parque Nacional Sierra de San Pedro Mártir. It might actually be the only convenient place to stay. Fortunately, it's also a nice comfortable ranch/lodge, and has some easily viewable lizards. The prettier one here was hanging out on the outside wall of the big dining room, where Lorrie Smith and Matt Cage also photographed it.
Meling Ranch, Baja California, MexicoMay 16, 2013
Black-tailed Brush Lizard (Urosaurus nigricauda)
One more Meling Ranch Urosaurus bade us farewell the next day from a parking lot bollard.
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