1. Order [Unassigned]
   1. Family Arenicolidae Johnston, 1835
   2. Family Capitellidae Grube, 1862
   3. Family Chaetopteridae Audouin & Milne Edwards, 1833
   4. Family Cossuridae Day, 1963
   5. Family Maldanidae Malmgren, 1867
   6. Family Opheliidae Malmgren, 1867
   7. Family Orbiniidae Hartman, 1942
   8. Family Paraonidae Cerruti, 1909
   9. Family Sabellariidae Johnston, 1865
   10. Family Scalibregmatidae Malmgren, 1867
   11. Family Travisiidae Hartmann-Schröder, 1971
   12. Family Anthostomea Kinberg, 1867 accepted as Orbiniidae Hartman, 1942 (based on a homonym and synonym, incorrectly Latinized)
   13. Family Ariciidae Audouin & Milne Edwards, 1833 accepted as Orbiniidae Hartman, 1942 (type genus Aricia is a replaced homonym, The next available genus name is Orbinia)
   14. Family Bogueidae Hartman & Fauchald, 1971 accepted as Rhodininae Arwidsson, 1906 (rank downgrade to synonymy to subfamily Rhodininae in Maldanidae)
   15. Family Hermellidae Malmgren, 1867 accepted as Sabellariidae Johnston, 1865 (based on a genus treated as a synonym of Sabellaria by Malmgren)
   16. Family Levinseniidae Mesnil & Caullery, 1898 accepted as Paraonidae Cerruti, 1909 (ICZN Opinion 1139 (1979) gives Paraonidae Cerruti 1909 precedence)
   17. Family Questidae Hartman, 1966 accepted as Questinae Hartman, 1966 (rank downgrade to Orbiniidae subfamily)
   18. Family Scalibregmidae Malmgren, 1867 accepted as Scalibregmatidae Malmgren, 1867 (superseded spelling)
   19. Family Telethusae Savigny, 1822 accepted as Arenicolidae Johnston, 1835 (Also later as Telethusidae. Unavailable as not formulated from an existing genus name)

1. Order Sabellida
2. Order Spionida
3. Order Terebellida
4. Order Capitellida (uncertain > nomen dubium, Superfluous name)
5. Suborder Chaetopteriformia (uncertain > nomen dubium, superfluous rank/name)
6. Order Cossurida (uncertain > nomen dubium, Superfluous name)
7. Order Opheliida (uncertain > nomen dubium, Superfluous name)
8. Order Orbiniida (uncertain > nomen dubium, Superfluous name)
9. Order Questida (uncertain > nomen dubium, Superfluous name)
10. Order Scolecidaformia (uncertain > nomen dubium, Superfluous (was order-level duplication of name Scolecida))

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