Rhinatrematidae – Beaked caecilians
Native to equatorial South America; widely regarded as the most basal family of caecilians
Found among the leaf litter of the tropical forests of northern South America, Family Rhinatrematidea is a group of primitive medium-sized caecilians commonly known as American-tailed caecilians or simply tailed caecilians. They usually have a grayish or purplish coloration, with some also characterized by a yellow lateral stripe.
They show several primitive characteristics compared to other caecilian families. For instance, they still possess true tails (vertebrae-supported extension of the body past the anus), external gills, and terminal mouths (most others have it on the underside of their heads). The presence of a terminal mouth and several other features imply they are not highly adapted for burrowing and may instead be terrestrial.
Also, unlike most other caecilians, they are egg-layers. The eggs hatch to give rise to free-living larvae.