little-lorayne-deactivated20140 asked: Hey Mark, you reblogged a couple of photosets of legless geckos a little bit ago, and in one of them, I (a nature interested laywoman) could definitely tell that they were geckos based on the pointed shape of their heads. But in the other, I wouldn't have been able to tell that they were geckos and not snakes. So how DO you spot the difference between legless geckos and snakes when they're not so pronounced?
Super great question!
Alright so I do it based off of instinct - I have seen enough of them now that I can easily distinguish between them without second thought.
BUT if you were to try to point out the differences, they are as follows:
- Pygopodids have external ear openings. NO snakes have these. This is a very good indicator.
- All pygopodids (legless geckos) have thick tongues (vs. thin, deeply bifurcated tongues in all serpents, which are more akin to the tongues of varanid lizards).
- Pygopodids probably don’t use their tongues for sensing their environments the way snakes do. If they behave in the way geckos do, they will lick the substrate occasionally to sense chemicals, but generally will use their tongues only during eating and cleaning. Snakes, on the other hand, as I’m sure you know, flick their tongues out to sense chemicals on the air, on a regular basis when active.
- In the case of scaly-foots (genus Pygopus), there is a reduced appendage that helps to distinguish them from snakes:
- Pygopodids have continuous scalation around their midbodies. So where higher snakes (i.e. not typhlopids and their allies) usually have wide, single ventral scales down the length of their bodies, pygopodids have several ventral scales per row:
Those are the most distinct features. So I hope they help!