Full reference: J. W. Dawson. 1863. Air-Breathers of the Coal Period: A Descriptive Account of the Remains of Land Animals Found in the Coal Formation of Nova Scotia with Remarks on their Bearing on Theories of the Formation of Coal and of the Origin of Species. Dawson Brothers, Montreal 81 p.
Sister taxa: Acherontiscidae, Adelogyrinus, Adelospondyli, Aistopoda, Asaphestera, Brachydectes, Diplocaulidae, Euryodus, Lysorophia, Microbrachis, Nectridea, Rhynchonkos, Saxonerpeton, Stegotretus, Utaherpeton