Perentie at Sydney Wildlife World
Perentie, varanus giganteus; a squamate
Scientific classification
Distribution of speciesEverywhere except Antarctica, Alaska, Greenland, and northern Russia

Squamata is the large, diverse order containing the lizards, snakes, and amphisbaenans. They are one of the few currently extant orders of reptiles, alongside crocodilians, turtles, and tuataras.

Traits Edit

Squamates will have a set of scales and/or scutes covering their entire body; unlike Chelonia, no part of their skin is exposed as it is always occupied by a scale or scute. Also notable of squamates is their movable quadrate bone; allowing them to open their mouths relatively wide. In snakes, the ability is more progressed, as they can open their mouths very wide to swallow animals very much bigger than their head (along with a trachea that can extend out of their mouth to keep breathing)[1].

Reproduction Edit

The reproductive organs of male squamates are, unlike crocodilians and chelonians, twin-lobed; the organ is called a hemipenis. Hemipenes are stored internally inside the male squamate's vent, to be everted when they need to mate. [2] Squamate eggs are soft and leathery (unlike crocodiles and most turtles), with the exception of the eggs of some geckos having a hard shell. [3]

Venom Edit

Squamates are unique among other reptiles in that they can deliver a venomous bite. Reptile venom is modified saliva, and in snakes, they are injected into their prey via hollow fangs. The quality of the fangs can be worn away over time, usually by the squirming and struggling of a prey animal.[4] The fangs however, will always grow back when lost [5]. Currently, there are only 3 lizards universally accepted to be venomous: the Gila monster, it's congener the Beaded lizard, and the Komodo dragon. For all three, the venom is rarely fatal to humans, and Gila monsters (and the Beaded lizard) have to chew into larger animals to get sufficient venom into the victim[6]. Komodo dragons, however, rely on their extremely potent septic bite to bring down even the largest of prey items.

Taxonomy Edit

Squamata has, traditionally, three suborders and holds about 4700 species.[7] The suborders, infraorders and familia are listed below:


References Edit