NATURAL HISTORY: The Leaf-Tailed Gecko!

Do you all remember when we went to the aquarium, and we got to see the herps that had come in for the Madagascar exhibit, and there were those leaf-tailed geckoes? They'd all stuck themselves up along the sides of the tank they were in, and they were super adorable clinging to the glass, right?

As it happens, they were only adorable because we couldn't see their eyes.

Doom arrives on setae-laden feet.

LEAF-TAILED GECKO STATS

• Genus: Uroplatus
• Species: 13
• Terrain: Arboreal
• Activity: Nocturnal
• Diet: Insects
• Weirdness: In spades

Leaf-tailed geckoes are all native to Madagascar, and there are 13 currently known species. They range in size from 4-12 inches, and like all geckoes, they are direct-developing amniotes. The fearsome-looking guy above is Uroplatus fimbriatus, and he is super angry; when he feels threatened, he will scream at you. Because it is daytime, his pupils have constricted to leave red-lined, soulless orbs. Leaf-tailed geckoes' pupils are highly constricted during the day because their eyes are phenomenally sensitive and are evolved to make them great night-time predators. At night, their pupils dilate to take up almost the whole visible surface of their eyes.

Crazy huge pupils.

Common to all Uroplatus are their flat tails and their overall tree-ish coloration, and they tend to have all kinds of weird texturing so that they look like bark. Their eyes are mottled so that they look like lichen. In addition, they have this fractal fringing all along their sides, and around their jaws and each of their toes, which disrupts their outline like nothing else. They are just incredible at camouflage. Here, try to find the U. sikorae in this picture.

Pro at camouflage.

As geckoes, these guys are arboreal, and they're nocturnal as well—not always the case with geckoes. They have an obscene number of very tiny teeth—around 130—which is super cool, although we don't know why they have all of them, because they eat insects, just like other geckoes. It would stand to reason that if their diet is similar to that of other geckoes, then their teeth should be similar, too. But they're not. So that's something new and fun to research if gecko dentition is of interest to you!

Some other physical characteristics of leaf-tailed geckoes:

• Super large head
• Widened toes, toe pads
• Reduced abdominal musculature
• 11 - 13 inscriptional ribs (as opposed to few/none)—inscriptional ribs are cartilaginous rib-like structures in the abdominal muscles; this possibly makes up for the reduced abdominal musculature
• Reduced depressor mandibulae--this is weird because they're scleroglossians, so they need some good chomping action to hunt, although they seem to be fine without it, so maybe it's reduced to keep the mass of the head down?
  
• Incipient secondary palate—there is just so much weird mouth stuff going on!

So here is the weird thing, though: we don't know what a lot of their anatomy is for; we have a serious dearth of knowledge of why they do anything, and we have been studying these guys pretty consistently since the mid-1600s. Here is a plate from the 1700s illustrating that point.

I am a total sucker for old-school scientific illustration. (This is by Lacépède and you should definitely check him out.)

MORE!

• Check out this slew of leaf-tailed gecko videos from Nature!
• This is one of the articles I read and it was just wonderful.
• Cited in that wonderful article is this paper which you should take a look at if you are super excited about leaf-tailed geckoes and/or have a lot of time-- it is long and really comprehensive.