; class Amphibia, order Urodela)
A family of permanently larval, aquatic amphibians which have an eel-shaped body, short fore limbs and tail, no hind limbs or pelvis, no teeth, and no eyelids. The jaws have horny plates. Gills are retained throughout life. Sirens swim and burrow in streams and ditches, and may occasionally move across land. There are three species, occurring in south-eastern USA.
Subjects: Zoology and Animal Sciences.