Happy World Lizard Day

There are more than 4,000 species of lizards. Many of them look quite different. For example, consider the Komodo dragon, a green iguana, and a fence lizard. These species have all evolved to look very different based on the very different environments they inhabit.

But what do you do when you run into a couple of species found in the same area that look very similar?

You turn to your field guide! This week’s challenge photo was submitted by Sven (CopperWings@sveniverson.bsky.social). I immediately knew it was either a greater earless lizard or a zebra-tailed lizard.

Both species have some pretty distinctive features. The male zebra-tailed lizards have stark and contrasty white and black bands on their tails, while greater earless lizards lack external ear holes.

Additionally, the ear holes on the zebra-tailed lizards are very noticeable. I didn’t see that in the reference photo above; however, it is hard to tell. Both species have skin folds where the ears are, and this can hide the ears on the zebra-tailed lizard.

I checked one of my favorite field guides, The Reptiles and Amphibians of Arizona, for any other distinguishing features. Both species have black bars going vertically along their bellies, but the bars are in different places.

These belly bars, are right below the front legs of the zebra-tailed lizard.

While greater earless lizards have the belly bars right in front of their back legs.

It’s hard to determine which species this is based on the difference in the photos provided.

Upon looking at the close-up photo, it seems like this individual has faint belly bands right below the front legs, and this photo (second image) of a zebra-tailed lizard that looks very similar to our reference photo, I’m going to go zebra-tailed lizard, Callisaurus draconoides .

I hope you #FoundThatLizard!

Finally, I’m wishing you a very happy #WorldLizardDay!