Opinions from A. Rõõmusoks 1964
- 'Camarotoechiidae belongs to Camarotoechiacea'
- 'Camerellidae belongs to Syntrophiacea'
- 'Cyclospira belongs to Cyclospiridae'
- 'Cyclospira levisulcata belongs to Cyclospira'
- 'Cyclospiridae belongs to Spiriferacea'
- 'Glyptorthinae belongs to Hesperorthidae'
- 'Glyptorthis belongs to Glyptorthinae'
- 'Glyptorthis plana belongs to Glyptorthis'
- 'Glyptorthis squamata belongs to Glyptorthis'
- 'Hebertella belongs to Plectorthinae'
- 'Hebertella estonica belongs to Hebertella'
- 'Hesperorthidae belongs to Orthacea'
- 'Hypsiptycha belongs to Orthorhynchulidae'
- 'Hypsiptycha procera belongs to Hypsiptycha'
- 'Onychoplecia belongs to Triplesiidae'
- 'Onychoplecia schmidti belongs to Onychoplecia'
- 'Orthorhynchulidae belongs to Rhynchonellacea'
- 'Parallelelasma belongs to Parallelelasmatidae'
- 'Parallelelasma kukrusensis belongs to Parallelelasma'
- 'Parallelelasmatidae belongs to Pentameracea'
- 'Plectorthidae belongs to Orthacea'
- 'Plectorthinae belongs to Plectorthidae'
- 'Ptychopleurella belongs to Glyptorthinae'
- 'Ptychopleurella pirguensis belongs to Ptychopleurella'
- 'Rostricellula belongs to Camarotoechiidae'
- 'Rostricellula nobilis belongs to Rostricellula' according to Oraspold 1956
- 'Stenocamara belongs to Stenocamarinae'
- 'Stenocamara biohermica belongs to Stenocamara'
- 'Stenocamarinae belongs to Camerellidae'
- 'Triplesiidae belongs to Triplesiacea'