EEK! Is that a lizard … or a snake?

Image via ItsNature.orgJust when you think you’ve got the world figured out, nature throws a curve ball.

When you look at this picture, what do you see? Is it a snake? Or is it a lizard?

This is a legless lizard.  It is one of several lizard species that, through evolution have either lost their limbs or reduced them to the point of being of absolutely no use for movement.

So then why is this “lizard” not a snake?

All snakes are legless but not all lizards have legs.

What other clues can you look for then?

CLUE #1

If you were to check out the skeleton of a legless lizard, you would quickly discover that they have retained the remnants of  the pectoral and pelvic girdles.  Snakes lack these.

CLUE #2

Look closely at the eyes … and in particular the eyelids.  Snakes have fixed eyelids and a clear spectacle covering their eyes.  The legless lizard actually has moveable eyelids.  Of course, keep in mind that there are some lizard species with fused eyelids and spectacle coverings such as a variety of geckos and skinks. How’s that for confusing matters?

(Not sure why there is a pic of lizard WITH legs in this video … but most are legless!)

CLUE #3

What is the most obvious visible difference between a snake and legless lizard?  The complete lack of an external ear on a snake.  Lizards, including legless lizards have an external ear.

CLUE #4

If you grab some lizards by their tail or threaten them, they may drop their tail (also called caudal autotomy) –  snakes on the other hand, cannot drop their tail.  When the tail falls off, it will twitch and wiggle on the ground. You might find yourself asking what purpose this serves?  It distracts the predator long enough, hopefully, for the lizard to escape.

Of course, I am not advising you to grab a lizard to check this theory please! A lizard that has lost its tail has lost a significant fat reserve and is more susceptible to stress.  And remember that stress can kill a reptile!

Internally, there are a few more differences between a snake and a legless lizard.  For example, lizards have a pair of lungs whereas snakes have a single lung.

Furthermore, a snake’s jaw is much more elastic compared to the jaw of a lizard.  Snakes can swallow large prey whole because of this, whereas a lizard cannot.

By Candace, SaveTheReptiles.com

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About Candace M Hansen

Wildlife advocate, conservationist and environmentalist.
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