trachystomata

from The Collaborative International Dictionary of English v.0.48
Trachystomata \Tra`chy*stom"a*ta\, n. pl. [NL., fr. Gr. ? rough
   + stoma.] (Zool.)
   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.
   [1913 Webster]
    

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