The Collaborative International Dictionary of English v.0.48:

Derotremata \Der`o*tre"ma*ta\, n. pl. [NL., fr. Gr. de`ros skin
   + ?, ?, hole.] (Zool.)
   The tribe of aquatic Amphibia which includes Amphiuma,
   Menopoma, etc. They have permanent gill openings, but no
   external gills; -- called also Cryptobranchiata. [Written
   also Derotrema.]
   [1913 Webster]