Trachystomata /(?)/

Tra·chy·stom·a·ta

Trachystomata

n. pl.
  1. An order of tailed aquatic amphibians, including Siren and Pseudobranchus. They have anterior legs only, are eel-like in form, and have no teeth except a small patch on the palate. The external gills are persistent through life. (Zool.)