I visit Mexico every year and my boyfriend calls these lizards "Queequoos" or something in Spanish (obviously without the QU spelling, haha). They are all over the areas that get more heat, but humidity seems unrelated (I've encountered them in both Oaxaca and Puerto Vallarta). They are very, very small and transparent, with huge size variances between adult and newborn. The babies are literally untouchable... you would kill them if they felt a gust of your breath, and I don't have any photos of them. The adults are almost as big as a leopard gecko adult, although quite a bit more slender and refined. I got some photos of a more developed baby that crawled onto my finger.

Any idea what these are? They seem like some type of nocturnal gecko. Sorry for the B/W shots, my partner likes to be really artsy.