| Family | Abrsiidae
Karanovic, 2008
| 1
1 | Genus
Species |
| Family | Anchimolgidae
Humes & Boxshall, 1996
| 31
141 | Genera
Species |
| Family | Anomoclausiidae
Gotto, 1964
| 1
1 | Genus
Species |
| Family | Antheacheridae
Sars, 1870
| 7
15 | Genera
Species |
| Family | Anthessiidae
Humes, 1986
| 8
72 | Genera
Species |
| Family | Bomolochidae
Claus, 1875
| 37
294 | Genera
Species |
| Family | Bradophilidae
Marchenkov, 2002
| 2
4 | Genera
Species |
| Family | Catiniidae ♰
Embleton, 1901
| 6
14 | Genera
Species |
| Family | Chondracanthidae
H. Milne-Edwards, 1840
| 76
378 | Genera
Species |
| Family | Choreftriidae
Uyeno, 2022
| 1
1 | Genus
Species |
| Family | Clausidiidae
Embleton, 1901
| 23
162 | Genera
Species |
| Family | Clausiidae
Giesbrecht, 1895
| 25
68 | Genera
Species |
| Family | Corallovexiidae
Stock, 1975
| 2
13 | Genera
Species |
| Family | Corycaeidae
Dana, 1852
| 12
146 | Genera
Species |
| Family | Echiurophilidae
Delamare-Deboutteville & Nunes-Ruivo, 1955
| 2
4 | Genera
Species |
| Family | Entobiidae
Ho, 1984
| 1
4 | Genus
Species |
| Family | Erebonasteridae
Humes, 1987
| 8
15 | Genera
Species |
| Family | Ergasilidae
von Nordmann, 1832
| 44
367 | Genera
Species |
| Family | Eunicicolidae
Sars, 1918
| 4
6 | Genera
Species |
| Family | Gadilicolidae
Boxshall & O´Reilly, 2015
| 1
1 | Genus
Species |
| Family | Gastrodelphyidae
List, 1889
| 8
15 | Genera
Species |
| Family | Giselinidae
Martínez Arbizu, 2000
| 2
4 | Genera
Species |
| Family | Herpyllobiidae
Hansen, 1892
| 10
40 | Genera
Species |
| Family | Hirodaiidae
Aneesh, Helna, Kumar & Maran, 2024
| 1
1 | Genus
Species |
| Family | Intramolgidae
Marchenkov & Boxshall, 1995
| 1
3 | Genus
Species |
| Family | Iveidae
Tung, Cheng, Lin, Ho, Kuo, Yu & Su, 2014
| 2
3 | Genera
Species |
| Family | Jasmineiricolidae
Boxshall, O´Reilly, Sikorski & Summerfield, 2015
| 1
1 | Genus
Species |
| Family | Kelleriidae
Humes & Boxshall, 1996
| 1
23 | Genus
Species |
| Family | Lamippidae
Joliet, 1882
| 14
94 | Genera
Species |
| Family | Leaniricolidae
Huys, 2016
| 1
1 | Genus
Species |
| Family | Lichomolgidae
Kossmann, 1877
| 48
307 | Genera
Species |
| Family | Lubbockiidae
Huys & Böttger-Schnack, 1997
| 7
22 | Genera
Species |
| Family | Macrochironidae
Humes & Boxshall, 1996
| 5
53 | Genera
Species |
| Family | Makrostrotidae
Huys, Fatih, Ohtsuka & Llewellyn-Hughes, 2011
| 1
2 | Genus
Species |
| Family | Mesoglicolidae
de Zulueta, 1911
| 1
1 | Genus
Species |
| Family | Micrallectidae
Huys, 2001
| 2
3 | Genera
Species |
| Family | Myicolidae
Yamaguti, 1936
| 9
37 | Genera
Species |
| Family | Mytilicolidae
Bocquet & Stock, 1957
| 5
17 | Genera
Species |
| Family | Nereicolidae
Claus, 1875
| 10
24 | Genera
Species |
| Family | Octopicolidae
Humes & Boxshall, 1996
| 1
9 | Genus
Species |
| Family | Oncaeidae
Giesbrecht, 1893
| 11
177 | Genera
Species |
| Family | Paralubbockiidae
Boxshall & Huys, 1989
| 1
1 | Genus
Species |
| Family | Philichthyidae
Vogt, 1877
| 11
135 | Genera
Species |
| Family | Philoblennidae
Izawa, 1976
| 6
12 | Genera
Species |
| Family | Pholoicolidae
| 1
1 | Genus
Species |
| Family | Phyllodicolidae
Delamare-Deboutteville & Laubier, 1961
| 2
3 | Genera
Species |
| Family | Pionodesmotidae
Bonnier, 1898
| 3
4 | Genera
Species |
| Family | Polyankyliidae
Ho & Kim, 1997
| 2
6 | Genera
Species |
| Family | Praxillinicolidae
Huys, 2016
| 1
2 | Genus
Species |
| Family | Pseudanthessiidae
Humes & Stock, 1972
| 8
83 | Genera
Species |
| Family | Rhynchomolgidae
Humes & Stock, 1972
| 49
354 | Genera
Species |
| Family | Sabelliphilidae
Gurney, 1927
| 9
72 | Genera
Species |
| Family | Saccopsidae
Lützen, 1964
| 5
11 | Genera
Species |
| Family | Sapphirinidae
Thorell, 1859
| 12
112 | Genera
Species |
| Family | Schminkepinellidae
Martínez Arbizu, 2006
| 4
8 | Genera
Species |
| Family | Serpulidicolidae
Stock, 1979
| 7
13 | Genera
Species |
| Family | Shiinoidae
Cressey, 1975
| 2
12 | Genera
Species |
| Family | Spiophanicolidae
Ho, 1984
| 1
4 | Genus
Species |
| Family | Splanchnotrophidae
Norman & Scott, 1906
| 10
38 | Genera
Species |
| Family | Strepidae
Cheng, Liu & Dai, 2016
| 1
1 | Genus
Species |
| Family | Synapticolidae
Humes & Boxshall, 1996
| 12
58 | Genera
Species |
| Family | Synaptiphilidae
Bocquet, 1953
| 4
10 | Genera
Species |
| Family | Taeniacanthidae
Wilson, 1911
| 28
173 | Genera
Species |
| Family | Telsidae
Ho, 1967
| 1
2 | Genus
Species |
| Family | Thamnomolgidae
Humes & Boxshall, 1996
| 3
5 | Genera
Species |
| Family | Urocopiidae
Humes & Stock, 1972
| 2
4 | Genera
Species |
| Family | Vahiniidae
Humes, 1967
| 2
2 | Genera
Species |
| Family | Ventriculinidae
Leigh-Sharpe, 1934
| 2
3 | Genera
Species |
| Family | Xarifiidae
Humes, 1960
| 8
104 | Genera
Species |
| Family | Xenocoelomatidae
Bresciani & Lützen, 1966
| 2
4 | Genera
Species |
