Acanthodoris pilosa (Abildgaard [in Müller], 1789) (additional source)
Actinia obtruncata Stimpson, 1853 (basis of record)
Actinia sipunculoides Stimpson, 1853 accepted as Edwardsia sipunculoides (Stimpson, 1853) (basis of record)
Actinostola callosa (Verrill, 1882) (additional source)
Adalaria proxima (Alder & Hancock, 1854) (additional source)
Aega psora (Linnaeus, 1758) (additional source)
Aetea anguina (Linnaeus, 1758) (additional source)
Alcyonidium polyoum (Hassall, 1841) (additional source)
Alcyonium digitatum Linnaeus, 1758 (additional source)
Alvania areolata (Stimpson, 1851) accepted as Tachyrhynchus reticulatus (Mighels & C. B. Adams, 1842) (additional source)
Alvania exarata (Stimpson, 1851) accepted as Onoba exarata (Stimpson, 1851) accepted as Onoba mighelsii (Stimpson, 1851) (basis of record)
Amaroucium glabrum Verrill, 1871 accepted as Aplidium glabrum (Verrill, 1871) (basis of record)
Amaroucium pallidum Verrill, 1871 accepted as Aplidium pallidum (Verrill, 1871) (basis of record)
Amaroucium spitzbergense (Hartmeyer, 1903) accepted as Aplidium spitzbergense Hartmeyer, 1903 (basis of record)
Amicula vestita (Broderip & G. B. Sowerby I, 1829) (additional source)
Ampharete acutifrons (Grube, 1860) (additional source)
Amphicteis gunneri (M. Sars, 1835) (additional source)
Amphilectus lobata (Montagu, 1814) accepted as Amphilectus ovulum (Schmidt, 1870) (source of synonymy)
Amphipholis squamata (Delle Chiaje, 1828) (additional source)
Amphiporeia lawrenciana Shoemaker, 1929 (additional source)
Amphiporus angulatus (Müller, 1774) (additional source)
Amphiporus bioculatus sensu Verrill, 1892 (additional source)
Amphiporus caecus Verrill, 1892 (basis of record)
Amphiporus frontalis Verrill, 1892 (additional source)
Amphiporus griseus (Stimpson, 1855) (basis of record)
Amphiporus groenlandicus Ørsted, 1843 (additional source)
Amphiporus ochraceus (Verrill, 1873) (basis of record)
Amphitrite johnstoni Malmgren, 1866 accepted as Neoamphitrite figulus (Dalyell, 1853) (additional source)
Anobothrus gracilis (Malmgren, 1866) (additional source)
Anomia aculeata Müller O.F., 1776 accepted as Heteranomia squamula (Linnaeus, 1758) (basis of record)
Anomia simplex d'Orbigny, 1853 (basis of record)
Aporrhais occidentalis (Beck, 1836) represented as Arrhoges occidentalis (Beck, 1836) (additional source)
Ascidia callosa Stimpson, 1852 (additional source)
Astarte borealis (Schumacher, 1817) (additional source)
Astarte castanea (Say, 1822) (additional source)
Astarte subaequilatera G. B. Sowerby II, 1854 (basis of record)
Astarte undata Gould, 1841 (additional source)
Atolla wyvillei Haeckel, 1880 (additional source)
Aulactinia stella (Verrill, 1864) (additional source)
Aurelia aurita (Linnaeus, 1758) (additional source)
Bolinopsis infundibulum (O.F. Müller, 1776) (additional source)
Boltenia echinata (Linnaeus, 1767) (additional source)
Boltenia ovifera (Linnaeus, 1767) (additional source)
Bopyroides hippolytes (Kröyer, 1838) (additional source)
Boreotrophon clathratus (Linnaeus, 1767) (additional source)
Boreotrophon truncatus (Strøm, 1768) (additional source)
Bostrichobranchus pilularis (Verrill, 1871) (basis of record)
Botryllus schlosseri (Pallas, 1766) (additional source)
Buccinum totteni Stimpson, 1865 (additional source)
Buccinum undatum Linnaeus, 1758 (additional source)
Bugula simplex Hincks, 1886 accepted as Bugulina simplex (Hincks, 1886) (additional source)
Bugula turrita (Desor, 1848) accepted as Crisularia turrita (Desor, 1848) (additional source)
Caberea ellisii (Fleming, 1814) (additional source)
Calliobdella van Beneden & Hesse, 1863 (additional source)
Calliobdella nodulifera (Malm, 1863) (additional source)
Carcinonemertes carcinophila (Kölliker, 1845) (additional source)
Cardita borealis Conrad, 1832 accepted as Cyclocardia borealis (Conrad, 1832) (basis of record)
Ceramaster granularis (Retzius, 1783) (additional source)
Cerebratulus lacteus (Leidy, 1851) (additional source)
Cerebratulus luridus accepted as Tarrhomyos luridus (Verrill, 1873) (additional source)
Cerebratulus marginatus Renier, 1804 (additional source)
Cerianthus borealis Verrill, 1873 accepted as Pachycerianthus borealis (Verrill, 1873) (additional source)
Chalinula loosanoffi (Hartman, 1958) (additional source)
Chelyosoma macleayanum Broderip & Sowerby, 1830 (additional source)
Chlamys islandica (O. F. Müller, 1776) (additional source)
Ciona intestinalis (Linnaeus, 1767) (additional source)
Clione limacina (Phipps, 1774) (additional source)
Cnemidocarpa mollis (Stimpson, 1852) (additional source)
Colus pubescens (A. E. Verrill, 1882) (additional source)
Colus pygmaeus (Gould, 1841) (additional source)
Colus stimpsoni (Mörch, 1868) (additional source)
Corophium tuberculatum Shoemaker, 1934 accepted as Monocorophium tuberculatum (Shoemaker, 1934) (additional source)
Cossura longocirrata Webster & Benedict, 1887 (additional source)
Craterolophus convolvulus (Johnston, 1835) (additional source)
Crella rosea (Topsent, 1892) represented as Crella (Yvesia) rosea (Topsent, 1892) (additional source)
Crisia cribraria Stimpson, 1854 (basis of record)
Crisia eburnea (Linnaeus, 1758) (additional source)
Crucibulum striatum (Say, 1826) (additional source)
Cryptosula pallasiana (Moll, 1803) (additional source)
Cuspidaria glacialis (Sars G. O., 1878) (additional source)
Cuthona concinna (Alder & Hancock, 1843) accepted as Cuthonella concinna (Alder & Hancock, 1843) (additional source)
Cyanea capillata (Linnaeus, 1758) (additional source)
Cyathura polita (Stimpson, 1855) (additional source)
Dendrobeania murrayana (Bean in Johnston, 1847) (additional source)
Dendrodoa carnea (Agassiz, 1850) (additional source)
Diadumene leucolena (Verrill, 1866) (basis of record)
Didemnum albidum (Verrill, 1871) (additional source)
Dioctophyma Lamouroux, 1824 accepted as Dioctophyme Collet-Meygret, 1802 (basis of record)
Dioctophyma renale (Goeze, 1782) accepted as Dioctophyme renale (Goeze, 1782) (basis of record)
Distaplia clavata (Sars, 1851) (additional source)
Drepanophorus lankesteri accepted as Hubrechtonemertes lankesteri (Hubrecht, 1887) accepted as Punnettia lankesteri (Hubrecht, 1887) (basis of record)
Drifa glomerata (Verrill, 1869) (additional source)
Echinarachnius parma (Lamarck, 1816) (additional source)
Edwardsia elegans Verrill, 1869 (additional source)
Edwardsia farinacea Verrill, 1869 accepted as Halcampa duodecimcirrata (Sars, 1851) (basis of record)
Edwardsia sipunculoides (Stimpson, 1853) (additional source)
Enoplus anisospiculus Nelson, Hopper & Webster, 1972 (basis of record)
Epitonium greenlandicum (Perry, 1811) accepted as Boreoscala greenlandica (Perry, 1811) (additional source)
Epizoanthus incrustatus Düben & Koren, 1847 accepted as Epizoanthus papillosus Johnston, 1842 (additional source)
Eubranchus exiguus (Alder & Hancock, 1848) (additional source)