Tuesday, July 25, 2006

A Couple of Tucson Lizards

July 8 - SONORAN SPOTTED WHIPTAIL (Cnemidophorus sonorae). I saw this lizard racing across our patio. Managed to grab a couple of shots of it before it ran under the gate. I looked up the web site Lizards of Arizona and tentatively identified it as a Sonoran Spotted Whiptail because of the spots running down the dark stripes on its back. All Sonoran Spotted Whiptails are female and breed by parthenogenesis. See Firefly Forest's excellent photos and description of the breeding habits of this lizard.
July 17 - WESTERN ZEBRA-TAILED LIZARD (Callisaurus draconoides rhodostictus). I looked out of my studio window one morning and saw dirt flying up out of a small hole. I went out to investigate and found this colourful lizard emerging.She rapidly headed for the fence about 40 feet away from me, but kindly stopped to pose for a couple of photos before running under. From photos on the Internet, I believe she's a sub-species of Western Zebra-tailed Lizard. There's a hint of bars under the tail and also two identifying bars on her side.
The zebra-tailed lizard has the peculiar habit of wagging its curled tail, which may serve to visually distract predators by drawing attention away from the lizard’s body and head. If a predator seizes the tail it easily detaches, a process known as autotomy. The tail has built-in fracture planes in the vertebrae to help it readily break off. The lizard grows back a cartilaginous replacement, which is shorter and has a different appearance than the original. (Arizona-Sonora Desert Museum)
This may be a pregnant female or one that's ready to mate:

Females of several lizard species exhibit color changes during breeding season. The “sand”lizards, for instance, develop bright orange or red areas on the different parts of the body. In some species this indicates readiness for breeding, while in others it is a signal to males that the female has already mated and is gravid (pregnant). (Arizona-Sonora Desert Museum)

4 comments:

LauraHinNJ said...

Neat lizards - can't quite imagine having them scurrying about in the yard, but...

The coloring on that last one is really something!

TDharma said...

I never knew lizards had such colorful underbellies. Great photos, Pam! You must be quick indeed with the camera.

Pam in Tucson said...

laura - We see quite a few lizards at this time of year, but I've photographed only a couple. They love the mid-day sun, but I'm not crazy enough to go outside to find them at that hour.

tdharma - I was lucky that these two weren't moving too fast. I tried to get some today, but they were under the fence before I could get anywhere near.

lené said...

LOVE YOUR LIZARDS, Pam!!! I saw many living near Houston and in the hill country of Texas, but I've never seen any as beautiful as these.