Amphisbaenia
Tropical, burrowing legless squamates derived from lizard ancestors. (A few species retain functioning front limbs.)
Like the unrelated caecilians, amphisbaenians feed on worms, insects, etc.
Key features:
- annulated body
- skin not attached to most of the body, allowing ́concertinaî locomotion
- strongly-built, short, broad head used for digging