Amphiporidae Oersted, 1844 (basis of record)
Amphiporus Ehrenberg, 1831 (basis of record)
Amphiporus angulatus (Müller, 1774) (basis of record)
Amphiporus bioculatus sensu Verrill, 1892 (basis of record)
Amphiporus groenlandicus Ørsted, 1843 (basis of record)
Amphiporus lactifloreus (Johnston, 1828) (basis of record)
Bdellonemertea accepted as Malacobdellidae Blanchard, 1847 (basis of record)
Bdellonemertini accepted as Malacobdellidae Blanchard, 1847 (basis of record)
Carcinonemertes Coe, 1902 (basis of record)
Carcinonemertidae Sumner, Osburn & Cole, 1913 (basis of record)
Cephalothricidae accepted as Cephalotrichidae McIntosh, 1873-1874 (basis of record)
Cephalothrix Örsted, 1843 (basis of record)
Cephalothrix linearis (Rathke, 1799) (basis of record)
Cerebratulidae accepted as Lineidae (basis of record)
Cerebratulus Renier, 1804 (basis of record)
Cerebratulus fuscus (McIntosh, 1874) (basis of record)
Cerebratulus marginatus Renier, 1804 (basis of record)
Cratenemertidae Friedrich, 1968 (basis of record)
Cyanophthalma Norenburg, 1986 (basis of record)
Cyanophthalma cordiceps (Jensen, 1878) sensu Norenburg, 1986 (basis of record)
Cyanophthalma obscura (Schultze, 1851) (basis of record)
Drepanophoridae (basis of record)
Drepanophorus Hubrecht, 1874 (basis of record)
Heteronemertea (basis of record)
Hoplonemertea (basis of record)
Hoplonemertini represented as Hoplonemertea (basis of record)
Lineidae (basis of record)
Lineus Sowerby, 1806 (basis of record)
Lineus ruber (Müller, 1774) (basis of record)
Lineus viridis (Müller, 1774) (basis of record)
Malacobdella Blainville, 1827 (basis of record)
Malacobdella grossa (Müller, 1776) (basis of record)
Malacobdellidae Blanchard, 1847 (basis of record)
Micrura Ehrenberg, 1828 (basis of record)
Monostilifera (basis of record)
Monostilifera incertae sedis (basis of record)
Nipponnemertes Friedrich, 1968 accepted as Nipponnemertes Gibson & Crandall, 1989 (basis of record)
Nipponnemertes pulcher (Johnston, 1837) accepted as Nipponnemertes pulchra (Johnston, 1837) (basis of record)
Oerstedia Quatrefages, 1846 (basis of record)
Oerstedia dorsalis (Abildgaard, 1806) (basis of record)
Palaeonemertea (basis of record)
Paradrepanophoridae Stiasny-Wijnhoff (basis of record)
Polystilifera (basis of record)
Procephalothrix Wijnhoff, 1913 accepted as Cephalothrix Örsted, 1843 (basis of record)
Punnettia Stiasny-Wijnhoff, 1926 (basis of record)
Reptantia (basis of record)
Tarrhomyos Riser, 1993 (basis of record)
Tenuilineus Riser, 1993 (basis of record)
Tetrastemma Ehrenberg, 1831 (basis of record)
Tetrastemma candidum (Müller, 1774) (basis of record)
Tetrastemma vermiculus (Quatrefages, 1846) (basis of record)
Tetrastemma vittigerum (Bürger, 1904) (basis of record)
Tetrastemmatidae Hubrecht, 1879 (basis of record)
Zygonemertes Montgomery, 1897 (basis of record)

Arctic Ocean for Amphiporus angulatus (Müller, 1774) 
Arctic Ocean for Amphiporus groenlandicus Ørsted, 1843 
Arctic Ocean for Lineus viridis (Müller, 1774) 
Arctic Ocean for Tetrastemma candidum (Müller, 1774) 
Baltic sea for Cyanophthalma obscura (Schultze, 1851) 
Black Sea for Cyanophthalma obscura (Schultze, 1851) 
European waters (ERMS scope) for Amphiporus angulatus (Müller, 1774) 
European waters (ERMS scope) for Amphiporus bioculatus sensu Verrill, 1892 
European waters (ERMS scope) for Amphiporus groenlandicus Ørsted, 1843 
European waters (ERMS scope) for Amphiporus lactifloreus (Johnston, 1828) 
European waters (ERMS scope) for Carcinonemertes carcinophila (Kölliker, 1845) 
European waters (ERMS scope) for Cephalothrix linearis (Rathke, 1799) 
European waters (ERMS scope) for Cerebratulus fuscus (McIntosh, 1874) 
European waters (ERMS scope) for Cerebratulus marginatus Renier, 1804 
European waters (ERMS scope) for Cyanophthalma cordiceps (Jensen, 1878) sensu Norenburg, 1986 
European waters (ERMS scope) for Cyanophthalma obscura (Schultze, 1851) 
European waters (ERMS scope) for Lineus ruber (Müller, 1774) 
European waters (ERMS scope) for Lineus viridis (Müller, 1774) 
European waters (ERMS scope) for Malacobdella grossa (Müller, 1776) 
European waters (ERMS scope) for Nipponnemertes pulcher (Johnston, 1837) 
European waters (ERMS scope) for Oerstedia dorsalis (Abildgaard, 1806) 
European waters (ERMS scope) for Tetrastemma candidum (Müller, 1774) 
European waters (ERMS scope) for Tetrastemma vermiculus (Quatrefages, 1846) 
European waters (ERMS scope) for Tetrastemma vittigerum (Bürger, 1904) 
Mediterranean Sea for Amphiporus lactifloreus (Johnston, 1828) 
Mediterranean Sea for Cephalothrix linearis (Rathke, 1799) 
Mediterranean Sea for Cerebratulus fuscus (McIntosh, 1874) 
Mediterranean Sea for Lineus ruber (Müller, 1774) 
Mediterranean Sea for Malacobdella grossa (Müller, 1776) 
Mediterranean Sea for Tetrastemma vermiculus (Quatrefages, 1846) 
Mediterranean Sea for Tetrastemma vittigerum (Bürger, 1904) 

 Authority

 for Tetrastemma robertianae McIntosh, 1874

Also mentioned as McIntosh, 1873/74 [details]

 Ecology

 for Carcinonemertes carcinophila (Kölliker, 1845)

on gills and eggs of crabs [details]

 Ecology

 for Emplectonema spongicola (Bergendal, 1903)

in sponges [details]

 Ecology

 for Gononemertes parasita Bergendal, 1900

in tunicates [details]

 Ecology

 for Malacobdella grossa (Müller, 1776)

in mantle cavity of bivalve molluscs [details]

 Ecology

 for Tetrastemma marionis Joubin, 1890

in ascidians [details]

 Ecology

 for Tetrastemma quadristriatum Langerhans, 1880

in ascidians [details]

 Ecology

 for Tetrastemma vittigerum (Bürger, 1904)

in ascidians [details]

 Habitat

 for Amphiporella baltica Friedrich, 1940

interstitial [details]

 Habitat

 for Balaenanemertes lobata (Joubin, 1906)

meso-bathypelagic [details]

 Habitat

 for Prosorhochmus claparedii Keferstein, 1862

mostly interstitial [details]

 Remark

 for Cryptonemertes actinophila (Bürger, 1904)

under pedal disc of sea anemones [details]

 Synonymy

 for Drepanophorus crassus nisidensis

Drepanophorus crassus nisidensis (partim) = Paradrepanophorus crassus [details]

 Synonymy

 for Tetrastemma stimpsoni Chernyshev, 1992

Prostoma stigmatum (partim) = Tetrastemma stimpsoni Tetrastemma stigmatum sensu Kulikova, 1988 = Tetrastemma ... [details]

 Taxonomy

 for Carinesta anglica Wijnhoff, 1912

Dubious species [details]

 Taxonomy

 for Cerebratulus barentsi Bürger, 1895

Dubious species [details]

 Taxonomy

 for Cerebratulus bivittatus Uljanin, 1870

Dubious species [details]

 Taxonomy

 for Cerebratulus croceus Grube, 1864

Dubious species [details]

 Taxonomy

 for Cerebratulus depressus Quatrefages, 1846

Dubious species [details]

 Taxonomy

 for Cerebratulus erythrorochma Joubin, 1902

Dubious species [details]

 Taxonomy

 for Emplectonema duoni (Joubin, 1890)

Dubious species [details]

 Taxonomy

 for Emplectonema marioni (Hubrecht, 1879)

Dubious species [details]

 Taxonomy

 for Lineus hubrechti (Langerhans, 1880)

Dubious species [details]

 Taxonomy

 for Micrura albifrons Timofeev, 1911

Dubious species [details]

 Taxonomy

 for Micrura rockalliensis Dollfus, 1924

Dubious species [details]

 Taxonomy

 for Micrura scotica Stephenson, 1911

Dubious species [details]

 Taxonomy

 for Nemertopsis capitulata Timofeev, 1911

Dubious species [details]

 Taxonomy

 for Nemertoscolex parasiticus Greeff, 1879

probably endoparasitic in echiuroids [details]

 Taxonomy

 for Oerstedia immutabilis (Riches, 1893)

Dubious species [details]

 Taxonomy

 for Oerstedia nigra (Riches, 1893)

Dubious species [details]

 Validity

 for Tetrastemma albicollis

Uncertainty about the Genusname [details]