Bathycotyle coryphaenae Yamaguti, 1938 accepted as Bathycotyle branchialis Darr, 1902 (original description)
Coeliotrema Yamaguti, 1938 (original description)
Coeliotrema thynni Yamaguti, 1938 (original description)
Didymocylindrus filiformis Ishii, 1935 (redescription)
Didymocystis abdominalis Yamaguti, 1938 (original description)
Didymocystis acanthocybii Yamaguti, 1938 (original description)
Didymocystis alalongae Yamaguti, 1938 (original description)
Didymocystis dissimilis Yamaguti, 1938 accepted as Oesophagocystis dissimilis (Yamaguti, 1938) Yamaguti, 1970 (original description)
Didymocystis miliaris Yamaguti, 1938 (original description)
Didymocystis opercularis Yamaguti, 1938 (original description)
Didymocystis submentalis Yamaguti, 1938 (original description)
Didymoproblema fusiforme Ishii, 1935 accepted as Didymocylindrus fusiformis (Ishii, 1935) Pozdnyakov, 1966 (redescription)
Didymozoon branchiale Yamaguti, 1938 accepted as Indodidymozoon branchiale (Yamaguti, 1938) Anderson & Cribb, 1994 (original description)
Didymozoon brevicolle Yamaguti, 1938 accepted as Indodidymozoon brevicolle (Yamaguti, 1938) Anderson & Cribb, 1994 (original description)
Didymozoon koti Yamaguti, 1938 accepted as Indodidymozoon koti (Yamaguti, 1938) Anderson & Cribb, 1994 (original description)
Didymozoon longicolle Ishii, 1935 (additional source)
Didymozoon spirale Yamaguti, 1938 accepted as Helicodidymozoon spirale (Yamaguti, 1938) Anderson & Cribb, 1994 (original description)
Diplotrema Yamaguti, 1938 accepted as Neodiplotrema Yamaguti, 1938 (original description)
Diplotrema pelamydis Yamaguti, 1938 accepted as Neodiplotrema pelamydis (Yamaguti, 1938) Yamaguti, 1970 (original description)
Gonapodasmius pacificus Yamaguti, 1938 accepted as Didymodiclinus pacificus (Yamaguti, 1938) Pozdnyakov, 1993 (original description)
Gonapodasmius pristipomatis (Yamaguti, 1934) Yamaguti, 1938 accepted as Didymodiclinus pristipomatis (Yamaguti, 1934) Pozdnyakov, 1994 (redescription)
Gonapodasmius pristipomatis (Yamaguti, 1934) Yamaguti, 1938 accepted as Didymodiclinus pristipomatis (Yamaguti, 1934) Pozdnyakov, 1994 (new combination reference)
Hirudinella spinulosa Yamaguti, 1938 accepted as Hirudinella ventricosa (Pallas, 1774) Baird, 1853 (original description)
Lobatozoum multisacculatum Ishii, 1935 (redescription)
Metanematobothrium Yamaguti, 1938 (original description)
Metanematobothrium guernei (Moniez, 1891) Yamaguti, 1938 (redescription)
Metanematobothrium guernei (Moniez, 1891) Yamaguti, 1938 (new combination reference)
Nematobothrium filiforme Yamaguti, 1934 (redescription)
Nematobothrium sabae Ishii, 1935 accepted as Nematobothrium filiforme Yamaguti, 1934 (source of synonymy)
Nematobothrium scombri (Taschenberg, 1879) Ishii, 1935 (redescription)
Paragonapodasmius Yamaguti, 1938 (original description)
Paragonapodasmius managatuwo Yamaguti, 1938 (original description)
Platocystis Yamaguti, 1938 (original description)
Platocystis alalongae Yamaguti, 1938 (original description)
Syncoelium katuwo Yamaguti, 1938 accepted as Copiatestes filiferus (Leuckart in Sars, 1885) Gibson & Bray, 1977 (original description)
Synodus japonicus (basis of record)
Tetrochetus hamadai Fukui & Ogata, 1935 (redescription)
Xystrias grigorjewi (Herzenstein, 1890) accepted as Eopsetta grigorjewi (Herzenstein, 1890) (basis of record)

Ariake Sea for Didymozoon spirale Yamaguti, 1938 
Japanese Exclusive Economic Zone for Didymocylindrus filiformis Ishii, 1935 
Japanese Exclusive Economic Zone for Didymozoon brevicolle Yamaguti, 1938 
Japanese Exclusive Economic Zone for Didymozoon koti Yamaguti, 1938 
Japanese Exclusive Economic Zone for Didymozoon longicolle Ishii, 1935 
Japanese Exclusive Economic Zone for Nematobothrium filiforme Yamaguti, 1934 
Japanese Exclusive Economic Zone for Nematobothrium scombri (Taschenberg, 1879) Ishii, 1935 
Japanese Exclusive Economic Zone for Tetrochetus hamadai Fukui & Ogata, 1935 
Japanese part of the Inland Sea for Didymozoon branchiale Yamaguti, 1938 
Japanese part of the Inland Sea for Gonapodasmius pristipomatis (Yamaguti, 1934) Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Bathycotyle coryphaenae Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Didymocystis abdominalis Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Didymocystis acanthocybii Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Didymocystis alalongae Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Didymocystis dissimilis Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Didymocystis miliaris Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Didymocystis opercularis Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Didymocystis submentalis Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Didymoproblema fusiforme Ishii, 1935 
Japanese part of the North Pacific Ocean for Diplotrema pelamydis Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Gonapodasmius pacificus Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Hirudinella spinulosa Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Metanematobothrium guernei (Moniez, 1891) Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Paragonapodasmius managatuwo Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Platocystis alalongae Yamaguti, 1938 
Japanese part of the North Pacific Ocean for Syncoelium katuwo Yamaguti, 1938 
Suruga Bay for Coeliotrema thynni Yamaguti, 1938