| Nominal Species (n = 410) | Present allocation (n = 395) | Ref. |
|---|---|---|
| Exogone acerata San Martín & Parapar, 1990 | Exogone acerata | 3477 |
| Anguillosyllis aciculata Maciolek, 2020 | Anguillosyllis aciculata | 3477 |
| Pionosyllis aciculata San Martín, 1990 | Pionosyllis aciculata | 7866 |
| Typosyllis aciculata Treadwell, 1945 | Syllis aciculata | 19 |
| Typosyllis aciculata Treadwell, 1945 | Typosyllis aciculata | 3477 |
| Typosyllis aciculata orientalis Imajima & Hartman, 1964 | Typosyllis aciculata | 3477 |
| Pionosyllis aciculogrossa San Martín, 1990 | Pionosyllis aciculogrossa | 7866 |
| Anguillosyllis acsara Maciolek, 2020 | Anguillosyllis acsara | 3477 |
| Sphaerosyllis acuiculata Perkins, 1981 | Sphaerosyllis acuiculata | 7866 |
| Trypanosyllis adamenteus Treadwell, 1941 | Trypanosyllis adamenteus | 8159 |
| Trypanosyllis aeolis Langerhans, 1879 | Trypanosyllis aeolis | 2663 |
| Haplosyllis agelas Uebelacker, 1982 | Haplosyllis agelas | 7866 |
| Autolytus alexandri Malmgren, 1867 | Epigamia alexandri | 3477 |
| Amblyosyllis algefnae Viguier, 1886 | Amblyosyllis lineata | 3477 |
| Typosyllis alosae San Martín, 1992 | Typosyllis alosae | 7866 |
| Syllis alternata Moore, 1908 | Syllis alternata | 8159 |
| Typosyllis alternata Moore, 1908 | Typosyllis alternata | 7866 |
| Syllis amica Quatrefages, 1866 | Syllis amica | 85340 |
| Petitia amphophthalma Siewing, 1956 | Neopetitia amphophthalma | 7866 |
| Amblyosyllis anae Aguado, Capa, Lago-Barcia et al., 2019 | Amblyosyllis anae | 3477 |
| Anguillosyllis andeepia Maciolek, 2020 | Anguillosyllis andeepia | 3477 |
| Opisthosyllis ankylochaeta Fauvel, 1921 | Opisthosyllis ankylochaeta | 3477 |
| Sphaerosyllis anoculata Hartmann-Schröder, 1980 | Sphaerosyllis anoculata | 7866 |
| Typosyllis anoculata Hartmann-Schröder, 1962 | Syllis anoculata | 3477 |
| Autolytus anoplos Monro, 1933 | Autolytus anoplos | 7866 |
| Pionosyllis anops Hartman, 1953 | Eusyllis maxima | 3477 |
| Amblyosyllis antoni Aguado, Capa, Lago-Barcia et al., 2019 | Amblyosyllis antoni | 3477 |
| Autolytus arboreus Westheide, 1974 | Autolytus arboreus | 8159 |
| Opisthosyllis arboricola Hartmann-Schröder, 1959 | Opisthosyllis arboricola | 8159 |
| Streptosyllis arenae Webster & Benedic | Streptosyllis arenae | 19 |
| Exogone arenosa Perkins, 1981 | Exogone arenosa | 7866 |
| Grubea arminii Langerhans, 1881 | Brania arminii | 2663 |
| Pionosyllis articulata Kudenov & Harris, 1995 | Pionosyllis articulata | 8159 |
| Syllides articulosus Ehlers, 1897 | Syllides articulosus | 19 |
| Eusyllis assimilis von Marenzeller, 1876 | Eusyllis assimilis | 19 |
| Exogone atlantica Perkins, 1981 | Exogone atlantica | 7866 |
| Pionosyllis Augeneri Hartmann-Schröder, 1979 | Pionosyllis augeneri | 7866 |
| Proceraea aurantiaca Claparède, 1868 | Proceraea aurantiaca | 2663 |
| Opisthosyllis australis Augener, 1913 | Opisthosyllis australis | 3477 |
| Sphaerosyllis austriaca Banse, 1959 | Sphaerosyllis austriaca | 3477 |
| Grubea balani Hartmann-Schröder, 1960 | Salvatoria balani | 2663 |
| Syllides bansei Perkins, 1981 | Syllides bansei | 7866 |
| Streptosyllis baolingi Ding & Westheide, 1994 | Streptosyllis baolingi | 82601 |
| Typosyllis barbata San Martín, 1992 | Typosyllis barbata | 7866 |
| Branchiosyllis belchiori Nascimento, Fukuda & Paiva, 2019 | Branchiosyllis belchiori | 3477 |
| Sphaerosyllis belizensis Russell, 1989 | Erinaceusyllis belizensis | 7866 |
| Syllis bella Chamberlin, 1919 | Syllis bella | 8159 |
| Typosyllis bella Chamberlin, 1919 | Typosyllis bella | 8159 |
| Syllis benguellana Day, 1963 | Syllis benguellana | 3477 |
| Autolytus beringianus Annenkova, 1934 | Autolytus beringianus | 3477 |
| Autolytus bicolor Rullier, 1972 | Autolytus bicolor | 3477 |
| Streptosyllis bidentata Southern, 1914 | Streptosyllis bidentata | 19 |
| Proceraea bifidentata Ben-Eliahu, 1977 | Proceraea bifidentata | 2663 |
| Typosyllis bifurcata Hartmann-Schröder, 1980 | Typosyllis bifurcata | 7866 |
| Sphaerosyllis bilobata Perkins, 1981 | Sphaerosyllis bilobata | 7866 |
| Haplosyllis bisetosa Hartmann-Schröder, 1960 | Syllis bisetosa | 2663 |
| Syllis bisetosa unspecified | Syllis bisetosa | 3477 |
| Anguillosyllis blakei Maciolek, 2020 | Anguillosyllis blakei | 3477 |
| Eusyllis blomstrandi Malmgren, 1867 | Eusyllis blomstrandi | 19 |
| Sphaerosyllis boeroi Musco, Çinar & Giangrande, 2005 | Sphaerosyllis boeroi | 3477 |
| Autolytus bondei Day, 1934 | Autolytus bondei | 19 |
| Sphaerosyllis brandhorsti Hartmann-Schröder, 1965 | Prosphaerosyllis brandhorsti | 19 |
| Exogone brasiliensis Fukuda, Menezes-Moura, Guimarães & Ruta, 2019 | Exogone brasiliensis | 3477 |
| Syllis brasiliensis McIntosh, 1885 | Syllis brasiliensis | 7866 |
| Exogone breviantennata Hartmann-Schröder, 1979 | Exogone breviantennata | 7866 |
| Dentatisyllis brevicirra Russell, 1992 | Dentatisyllis brevicirra | 7866 |
| Parapionosyllis brevicirra Day, 1954 | Parapionosyllis brevicirra | 3477 |
| Sphaerosyllis brevicirra Hartmann-Schröder, 1960 | Prosphaerosyllis brevicirra | 2663 |
| Autolytus brevicirrata Winternitz, 1936 | Autolytus brevicirrata | 7866 |
| Sphaerosyllis brevidentata Perkins, 1981 | Sphaerosyllis brevidentata | 7866 |
| Odontosyllis brevipes Hartmann-Schröder, 1959 | Odontosyllis brevipes | 8159 |
| Plakosyllis brevipes Hartmann-Schröder, 1956 | Plakosyllis brevipes | 2663 |
| Sylline brevipes Claparède, 1864 | Exogone brevipes | 2663 |
| Anguillosyllis bruneiensis Maciolek, 2020 | Anguillosyllis bruneiensis | 3477 |
| Opisthodonta brunnea Langerhans, 1879 | Opisthodonta brunnea | 7866 |
| Opisthosyllis brunnea Langerhans, 1879 | Opisthosyllis brunnea | 19 |
| Sphaerosyllis californiensis Hartman, 1966 | Sphaerosyllis californiensis | 8159 |
| Exogone campoyi San Martín, Ceberio & Aguirrezabalaga, 1996 | Exogone campoyi | 3477 |
| Exogone canyonincolae Sardá, Gil, Taboada & Gili, 2009 | Exogone canyonincolae | 85340 |
| Sphaerosyllis capensis Day, 1953 | Sphaerosyllis capensis | 19 |
| Exogone caribensis San Martín, 1991 | Exogone caribensis | 7866 |
| Anguillosyllis carolina Maciolek, 2020 | Anguillosyllis carolina | 3477 |
| Syllis castroviejoi Capa, San-Martín & López,2001 | Syllis castroviejoi | 8159 |
| Sphaerosyllis centroamerica Hartmann-Schröder, 1959 | Sphaerosyllis centroamerica | 7866 |
| Sphaerosyllis centroamericana Hartmann-schroeder, 1959 | Sphaerosyllis centroamericana | 19 |
| Eusyllis ceylonica Augener, 1926 | Eusyllis ceylonica | 3477 |
| Haplosyllis chamaeleon Laubier, 1960 | Haplosyllis chamaeleon | 3477 |
| Autolytus charcoti Gravier, 1906 | Epigamia charcoti | 19 |
| Megasyllis chiki San Martín, Lucas & Westheide, 2021 | Megasyllis chiki | 3477 |
| Syllis cirropunctata Michel, 1909 | Branchiosyllis cirropunctata | 19 |
| Dioplosyllis cirrosa Gidholm, 1962 | Dioplosyllis cirrosa | 3477 |
| Sphaerosyllis claparedei Ehlers, 1864 | Sphaerosyllis claparedei | 3477 |
| Amblyosyllis clarae Aguado, Capa, Lago-Barcia et al., 2019 | Amblyosyllis clarae | 3477 |
| Syllis clavata Clapaède, 1863 | Salvatoria clavata | 2663 |
| Virchowia clavata Langerhans, 1879 | Virchowia clavata | 3477 |
| Exogone clavator Ehlers, 1913 | Exogone clavator | 2663 |
| Syllis closterobranchia Schmarda, 1861 | Syllis armillaris | 3477 |
| Trypanosyllis coeliaca Claparède, 1868 | Trypanosyllis coeliaca | 7866 |
| Exogone cognettii Castelli, Bandalamenti & Lardicci, 1987 | Exogone cognettii | 3477 |
| Pionosyllis comosa Gravier, 1906 | Pionosyllis comosa | 87389 |
| Pionosyllis compacta Malmgren, 1867 | Pionosyllis compacta | 19 |
| Syllis compacta Gravier, 1900 | Syllis compacta | 3477 |
| Pionosyllis confusa Hartmann-Schröder, 1960 | Nudisyllis pulligera | 2663 |
| Spermosyllis confusa Hartmann-Schröder, 1960 | Spermosyllis confusa | 2663 |
| Autolytus convolutus Cognetti, 1953 | Myrianida convoluta | 7866 |
| Syllides convolutus Webster & Benedict, 1884 | Syllides convolutus | 3477 |
| Opisthosyllis corallicola Hartmann-Schröder, 1965 | Opisthosyllis corallicola | 8159 |
| Syllis corallicola Verrill, 1900 | Syllis corallicola | 1398 |
| Syllis corallicoloides Augener, 1922 | Syllis corallicoloides | 8159 |
| Typosyllis corallicoloides Augener, 1924 | Typosyllis corallicoloides | 7866 |
| Syllides cornuta Rathke, 1843 | Langerhansia cornuta | 75097 |
| Syllis cornuta Rathke, 1843 | Syllis cornuta | 19 |
| Autolytus cornutus Agassiz, 1862 | Proceraea cornuta | 3477 |
| Myrianida crassicirrata Hartmann-Schroeder, 1965 | Myrianida crassicirrata | 19 |
| Typosyllis crassicirrata Treadwell, 1925 | Typosyllis crassicirrata | 19 |
| Paraprocerastea crocantinae San Martín & Alós, 1989 | Paraprocerastea crocantinae | 3477 |
| Syllis cruzi Núñez & San Martín, 1991 | Syllis cruzi | 3477 |
| Odontosyllis ctenostoma Claparede, 1868 | Odontosyllis ctenostoma | 19 |
| Pseudosyllides curacaoensis Augener, 1927 | Pseudosyllides curacaoensis | 7866 |
| Pionosyllis dangrigae Russell, 1992 | Pionosyllis dangrigae | 7866 |
| Anguillosyllis denaria Maciolek, 2020 | Anguillosyllis denaria | 3477 |
| Autolytus dentalius Imajima, 1966 | Myrianida dentalia | 7866 |
| Miscellania dentata Martin, Alós & Sardá, 1990 | Miscellania dentata | 3477 |
| Typosyllis dentata Hartmann-Schröder, 1960 | Typosyllis dentata | 2663 |
| Odontosyllis detecta Augener, 1913 | Odontosyllis detecta | 7866 |
| Branchiosyllis diazi Rioja, 1959 | Branchiosyllis diazi | 7866 |
| Sphaerosyllis dieteri San Martín, Lucas & Westheide, 2021 | Sphaerosyllis dieteri | 3477 |
| Pionosyllis dionisi Núñez & San Martín, 1991 | Pionosyllis dionisi | 3477 |
| Syllis dominguezi San Martín, Lucas & Westheide, 2021 | Syllis dominguezi | 3477 |
| Amblyosyllis dorsigera (Claparède, 1864) | Amblyosyllis spectabilis | 7866 |
| Pterosyllis dorsigera Claparède, 1864 | Amblyosyllis spectabilis | 123541 |
| Odontosyllis dugesiana Claparède, 1864 | Odontosyllis dugesiana | 3477 |
| Syllides edentatus Westheide, 1974 | Syllides edentatus | 3477 |
| Eusyllis edenticulata Pillai, 1965 | Eusyllis edenticulata | 82601 |
| Anoplosyllis edentula Claparède, 1868 | Anoplosyllis edentula | 3477 |
| Autolytus edwardsi Saint-joseph, 1887 | Myrianida edwardsi | 19 |
| Anguillosyllis elegantissima Maciolek, 2020 | Anguillosyllis elegantissima | 3477 |
| Amblyosyllis emilioi Aguado, Capa, Lago-Barcia et al., 2019 | Amblyosyllis emilioi | 3477 |
| Anguillosyllis enneapoda Maciolek, 2020 | Anguillosyllis enneapoda | 3477 |
| Odontosyllis enopla Verrill, 1900 | Odontosyllis enopla | 7866 |
| Pionosyllis epipharynx Hartman, 1953 | Eusyllis maxima | 3477 |
| Sphaerosyllis erinaceus Claparède, 1863 | Erinaceusyllis erinaceus | 7866 |
| Syllis escribanoi San Martín, Lucas & Westheide, 2021 | Syllis escribanoi | 3477 |
| Typosyllis exilis Gravier, 1900 | Branchiosyllis exilis | 3477 |
| Exogone exmouthensis Hartmann-Schröder, 1980 | Exogone exmouthensis | 7866 |
| Autolytus fallax Malmgren, 1867 | Proceraea cornuta | 3477 |
| Proceraea fasciata Langerhans, 1879 | Proceraea fasciata | 8159 |
| Syllis fasciata Malamgren, 1867 | Syllis fasciata | 3477 |
| Exogone fauveli Cognetti, 1961 | Exogone fauveli | 3477 |
| Syllis ferrani Alós & San Martín, 1987 | Syllis ferrani | 3477 |
| Langerhansia ferrugina Langerhans, 1881 | Paraehlersia ferrugina | 75097 |
| Syllis filiformis Rullier, 1972 | Syllis filiformis | 3477 |
| Prosphaerosyllis fittoni San Martín, Lucas & Westheide, 2021 | Prosphaerosyllis fittoni | 3477 |
| Parapionosyllis floridana San Martín, 1991 | Parapionosyllis floridana | 7866 |
| Syllides floridanus Perkins, 1981 | Syllides floridanus | 7866 |
| Pterosyllis formosa Claparede, 1863 | Amblyosyllis spectabilis | 123541 |
| Odontosyllis freycinetensis Augener, 1913 | Odontosyllis freycinetensis | 3477 |
| Exogone furcifera Eliason, 1868 | Exogone furcifera | 19 |
| Brania gallagheri Perkins, 1981 | Brania gallagheri | 7866 |
| Exogone gambiae Lanera, Sordino & San Martin, 1994 | Exogone gambiae | 3477 |
| Exogone gemmifera Pagenstecher, 1862 | Exogone gemmifera | 7866 |
| Trypanosyllis gemmipara Johnson, 1901 | Trypanosyllis gemmipara | 7866 |
| Pionosyllis gesae Perkins, 1981 | Pionosyllis gesae | 7866 |
| Odontosyllis gibba Claparède, 1863 | Odontosyllis gibba | 19 |
| Autolytus gibber Ehlers, 1897 | Autolytus maclearanus | 3477 |
| Pionosyllis gigantea Moore, 1908 | Pionosyllis gigantea | 8159 |
| Syllis gigantea McIntosh, 1885 | Trypanosyllis gigantea | 3477 |
| Sphaerosyllis glandulata Perkins, 1981 | Sphaerosyllis glandulata | 7866 |
| Brania glandulosa Hartmann-Schröder, 1980 | Brania glandulosa | 7866 |
| Exogone glandulosa Rioja, 1943 | Exogone glandulosa | 8159 |
| Typosyllis glarearia Westheide, 1974 | Typosyllis glarearia | 8159 |
| Syllides gomezi San Martín, 1990 | Syllides gomezi | 7866 |
| Branchiosyllis gonzaguinhai Nascimento, Fukuda & Paiva, 2019 | Branchiosyllis gonzaguinhai | 3477 |
| Grubea gracilis Hartmann-Schröder, 1960 | Grubeosyllis gracilis | 2663 |
| Syllis gracilis Grube, 1840 | Syllis gracilis | 19 |
| Amblyosyllis granosa Ehlers, 1897 | Amblyosyllis granosa | 7866 |
| Odontosyllis gravelyi Fauvel, 1928 | Odontosyllis gravelyi | 2663 |
| Sphaerosyllis gravinae Somaschini & San Martín, 1994 | Sphaerosyllis gravinae | 3477 |
| Eusyllis habei Imajima, 1966 | Eusyllis habei | 19 |
| Anguillosyllis hadra Maciolek, 2020 | Anguillosyllis hadra | 3477 |
| Streptosyllis hainanensis Ding & Westheide, 1994 | Streptosyllis hainanensis | 82601 |
| Procerastea halleziana Malaquin, 1893 | Procerastea halleziana | 19 |
| Anguillosyllis hampsoni Maciolek, 2020 | Anguillosyllis hampsoni | 3477 |
| Typosyllis hawaiiensis Hartmann-Schroeder, 1965 | Typosyllis hawaiiensis | 19 |
| Exogone heboides Ben-Eliahu, 1977 | Exogone heboides | 2663 |
| Amblyosyllis hectori Aguado, Capa, Lago-Barcia et al., 2019 | Amblyosyllis hectori | 3477 |
| Thylaciphorus hessii Quatrefages, 1866 | Amblyosyllis spectabilis | 123541 |
| Anguillosyllis hessleri Maciolek, 2020 | Anguillosyllis hessleri | 3477 |
| Syllis heterochaeta Moore, 1909 | Syllis heterochaeta | 3477 |
| Eusyllis heterocirrata Hartmann-Schröder, 1959 | Eusyllis heterocirrata | 8159 |
| Typosyllis heterocirrata Hartmann-Schröder, 1960 | Typosyllis heterocirrata | 2663 |
| Odontosyllis heterodonta Góngora-Garza & de León-González, 1993 | Odontosyllis heterodonta | 8159 |
| Streptospinigera heteroseta Kudenov, 1983 | Streptospinigera heteroseta | 7866 |
| Exogone heterosetosa McIntosh, 1885 | Exogone heterosetosa | 3477 |
| Eusyllis homocirrata Hartmann-Schröder, 1958 | Eusyllis homocirrata | 7866 |
| Syllis hyalina Grube, 1863 | Syllis hyalina | 3477 |
| Typosyllis hyllebergi Licher, 2000 | Typosyllis hyllebergi | 2663 |
| Sphaerosyllis hystrix Claparède, 1863 | Sphaerosyllis hystrix | 19 |
| Amblyosyllis idae Aguado, Capa, Lago-Barcia et al., 2019 | Amblyosyllis idae | 3477 |
| Cryptochaetosyllis imitatio Jimi, Britayev & Martin in Jimi et al., 2024 | Cryptochaetosyllis imitatio | 131550 |
| Amblyosyllis immatura Langerhans, 1879 | Amblyosyllis spectabilis | 123541 |
| Parasphaerosyllis indica Monro, 1937 | Parasphaerosyllis indica | 19 |
| Autolytus inermis Saint Joseph, 1887 | Myrianida inermis | 19 |
| Trypanosyllis inglei Perkins, 1981 | Trypanosyllis inglei | 7866 |
| Anguillosyllis inornata Maciolek, 2020 | Anguillosyllis inornata | 3477 |
| Eusyllis intermedia Saint-joseph, 1887 | Eusyllis intermedia | 19 |
| Opisthosyllis japonica Imajima, 1966 | Opisthosyllis japonica | 8159 |
| Syllides japonica edentata Westheide, 1974 | Syllides edentatus | 3477 |
| Syllides japonicus Imajima, 1966 | Syllides japonicus | 85340 |
| Parexogone javieri San Martín, Lucas & Westheide, 2021 | Parexogone javieri | 3477 |
| Autolytus juventudensis San Martín, 1994 | Autolytus juventudensis | 7866 |
| Syllis kabilica Ben-Eliahu, 1977 | Syllis kabilica | 3477 |
| Syllis kai San Martín, Lucas & Westheide, 2021 | Syllis kai | 3477 |
| Eusyllis kerguelensis McIntosh, 1885 | Eusyllis kerguelensis | 3477 |
| Salvatoria kerguelensis McIntosh, 1885 | Brania kerguelensis | 3477 |
| Syllis kinbergiana Haswell, 1886 | Megasyllis inflata | 3477 |
| Ramisyllis kingghidorahi Aguado, et al., 2022 | Ramisyllis kingghidorahi | 3477 |
| Syllis krohni Ehlers, 1864 | Syllis krohni | 3477 |
| Eusyllis kupfferi Langerhans, 1879 | Eusyllis kupfferi | 3477 |
| Parapionosyllis labronica Cognetti, 1965 | Parapionosyllis labronica | 3477 |
| Opisthosyllis laevis Day, 1957 | Opisthosyllis laevis | 3477 |
| Eusyllis lamelligera Marion & Bobretzky, 1875 | Eusyllis lamelligera | 7866 |
| Pionosyllis lamelligera Saint-Joseph, 1886 | Synmerosyllis lamelligera | 86631 |
| Autolytus langerhansi Gidholm, 1967 | Myrianida langerhansi | 19 |
| Grubea limbata Claparède, 1868 | Salvatoria limbata | 2663 |
| Amblyosyllis lineata Grube, 1863 | Amblyosyllis lineata | 3477 |
| Sphaerosyllis longicauda Wbster & Benedict, 1887 | Sphaerosyllis longicauda | 7866 |
| Alluaudella longicirrata Mohammad, 1973 | Alluaudella longicirrata | 2663 |
| Opisthosyllis longicirrata Monro, 1939 | Opisthosyllis longicirrata | 19 |
| Exogone longicornis Westheide, 1974 | Exogone longicornis | 8159 |
| Odontosyllis longicornis Hartmann-Schröder, 1960 | Odontosyllis longicornis | 2663 |
| Opisthodonta longidentata San Martín, 1991 | Opisthodonta longidentata | 7866 |
| Synsyllis longigularis Verrill, 1900 | Synsyllis longigularis | 7866 |
| Odontosyllis longigulata Perkins, 1981 | Odontosyllis longigulata | 7866 |
| Sphaerosyllis longilamina Russell, 1989 | Sphaerosyllis longilamina | 7866 |
| Syllis longisegmentata Grube, 1857 | Syllis longisegmentata | 7866 |
| Exogone longispinulata San Martín, 1991 | Exogone longispinulata | 7866 |
| Syllis longissima Gravier, 1900 | Syllis longissima | 8159 |
| Exogone lopezi San Martín, Ceberio & Aguirrezabalaga, 1996 | Exogone lopezi | 3477 |
| Exogone lourei Berkeley & Berkeley, 1938 | Exogone lourei | 7866 |
| Odontosyllis luminosa San Martín, 1990 | Odontosyllis luminosa | 7866 |
| Typosyllis lunaris Imajima, 1966 | Typosyllis lunaris | 2663 |
| Pionosyllis luquei San Martín, 1990 | Pionosyllis luquei | 7866 |
| Parautolytus luzonensis Pillai, 1965 | Parautolytus luzonensis | 82601 |
| Autolytus maclearanus McIntosh, 1885 | Autolytus maclearanus | 3477 |
| Proceraea macrophthalma Marenzeller, 1875 | Epigamia macrophthalma | 3477 |
| Typosyllis maculata Imajima, 1966 | Typosyllis maculata | 82601 |
| Amblyosyllis madeirensis Langerhans, 1879 | Amblyosyllis madeirensis | 7866 |
| Sphaerosyllis magnidentata Perkins, 1981 | Sphaerosyllis magnidentata | 7866 |
| Syllis magnipectinis Storch, 1967 | Typosyllis magnipectinis | 2663 |
| Parasphaerosyllis malimalii Capa, San-Martín & López,2001 | Parasphaerosyllis malimalii | 8159 |
| Dentatisyllis mangalis Russell, 1995 | Dentatisyllis mangalis | 7866 |
| Salvatoria marielleae Nascimento, Fukuda & Paiva in Nascimento et al., 2021 | Salvatoria marielleae | 3477 |
| Fauvelia martinensis Gravier, 1900 | Fauvelia martinensis | 19 |
| Pionosyllis maxima Monro, 1930 | Eusyllis maxima | 3477 |
| Brania mediodentata Westheide, 1974 | Brania mediodentata | 7866 |
| Autolytus megodon Saint-joseph, 1887 | Autolytus megodon | 19 |
| Exogone meridionalis Cognetti, 1955 | Exogone meridionalis | 3477 |
| Ehlersia mexicana Rioja, 1960 | Ehlersia mexicana | 7866 |
| Pseudosyllides mexicana Góngora-Garza & de León-González, 1993 | Pseudosyllides mexicana | 8159 |
| Typosyllis microoculata Hartmann-Schroeder, 1965 | Typosyllis microoculata | 19 |
| Exogone microtentaculata Westheide, 1974 | Exogone microtentaculata | 8159 |
| Sphaerosyllis minima Hartmann-Schröder, 1960 | Sphaerosyllis minima | 2663 |
| Exogone minuscula Hartman, 1953 | Parexogone minuscula | 3477 |
| Autolytus misakiensis Imajima, 1966 | Proceraea misakiensis | 2663 |
| Opisthodontha mitchelli Kudenov & Harris, 1995 | Opisthodontha mitchelli | 8159 |
| Typosyllis monilata Imajima, 1966 | Typosyllis monilata | 82601 |
| Opisthodonta morena Langerhans, 1879 | Opisthodonta morena | 19 |
| Autolytus multidentatus Hartmann-Schröder, 1959 | Autolytus multidentatus | 8159 |
| Autolytus multidenticulatus Westheide, 1974 | Autolytus multidenticulatus | 8159 |
| Exogone naidina Ørsted, 1845 | Exogone naidina | 19 |
| Exogone naidinoides Westheide, 1974 | Exogone naidinoides | 7866 |
| Syllis neglecta Ehrenberg & Grube, 1869 | Typosyllis neglecta | 2663 |
| Procerastea nematodes Langerhans, 1884 | Procerastea nematodes | 19 |
| Syllis nigricirris Grube, 1863 | Syllis nigricirris | 3477 |
| Amblyosyllis nigrolineata Okada, 1934 | Amblyosyllis nigrolineata | 3477 |
| Grubeosyllis nitidula Verrill, 1900 | Grubeosyllis nitidula | 7866 |
| Salvatoria nitiduloides Nascimento, Fukuda, Paresque, Nogueira & Paiva, 2021 | Salvatoria nitiduloides | 3477 |
| Branchiosyllis noviseta Russell, 1991 | Branchiosyllis noviseta | 7866 |
| Grubea nuchalata Hartmann-Schröder, 1960 | Grubeosyllis nuchalata | 2663 |
| Opisthosyllis nuchalis Verrill, 1900 | Opisthosyllis nuchalis | 3477 |
| Typosyllis nuchalis Hartmann-Schröder, 1960 | Syllis nuchalis | 2663 |
| Pionosyllis nutrix Monro, 1936 | Salvatoria nutrix | 3477 |
| Exogone occidentalis Westheide, 1974 | Exogone occidentalis | 7866 |
| Dioplosyllis octodentata Perkins, 1981 | Dioplosyllis octodentata | 7866 |
| Odontosyllis octodentata Treadwell, 1917 | Odontosyllis octodentata | 7866 |
| Branchiosyllis oculata Ehlers, 1887 | Branchiosyllis oculata | 7866 |
| Typosyllis ornata Hartmann-Schroeder, 1965 | Typosyllis ornata | 19 |
| Amblyosyllis ovei Aguado, Capa, Lago-Barcia et al., 2019 | Amblyosyllis ovei | 3477 |
| Sphaerosyllis ovigera Langerhans, 1879 | Sphaerosyllis ovigera | 19 |
| Branchiosyllis pacifica Rioja, 1941 | Branchiosyllis pacifica | 7866 |
| Syllis palifica Ehlers, 1901 | Syllis palifica | 8159 |
| Opisthosyllis papillosa Hartmann-Schröder, 1960 | Opisthosyllis papillosa | 19 |
| Syllides papillosa Hartmann-Schröder, 1965 | Syllides papillosa | 7866 |
| Autolytus paradoxus Saint-joseph, 1887 | Autolytus paradoxus | 19 |
| Syllis parapari San Martín & López, 2000 | Syllis parapari | 3477 |
| Proceraea paraurantiaca Nygren, 2004 | Proceraea paraurantiaca | 3477 |
| Syllis parturiens Haswell, 1920 | Typosyllis parturiens | 2663 |
| Trypanosyllis parvidentata Perkins, 1981 | Trypanosyllis parvidentata | 7866 |
| Sphaerosyllis parvoculata Russell, 1989 | Sphaerosyllis parvoculata | 7866 |
| Typosyllis patriciae Hartmann-Schröder, 1981 | Typosyllis patriciae | 3477 |
| Parapionosyllis paucicirra Hartmann-Schröder, 1960 | Parapionosyllis paucicirra | 2663 |
| Syllis pectinans Haswell, 1920 | Syllis pectinans | 3477 |
| Paratyposyllis peresi Laubier, 1968 | Paratyposyllis peresi | 3477 |
| Sphaerosyllis perkinsi Riser, 1991 | Sphaerosyllis perkinsi | 7866 |
| Sphaerosyllis perspicax Ehlers, 1912 | Sphaerosyllis perspicax | 89855 |
| Streptosyllis pettibonae Perkins, 1981 | Streptosyllis pettibonae | 7866 |
| Odontosyllis phosphorea Moore, 1909 | Odontosyllis phosphorea | 8159 |
| Proceraea picta Ehlers, 1864 | Proceraea picta | 19 |
| Nereis pinnigera Montagu, 1808 | Myrianida pinnigera | 75097 |
| Sphaerosyllis pirifera Claparède, 1868 | Sphaerosyllis pirifera | 7866 |
| Sphaerosyllis piriferopsis Perkins, 1981 | Sphaerosyllis piriferopsis | 7866 |
| Syllis plessisi Rullier, 1972 | Branchiosyllis exilis | 3477 |
| Odontosyllis polyodonta Saint-joseph, 1887 | Odontosyllis polyodonta | 19 |
| Syllis pontxioi San Martín & López, 2000 | Syllis pontxioi | 3477 |
| Trypanosyllis prampramensis Augener, 1918 | Trypanosyllis prampramensis | 7866 |
| Pionosyllis procera Hartman, 1965 | Pionosyllis procera | 7866 |
| Syllis prolifera Krohn, 1852 | Syllis prolifera | 3477 |
| Syllis prolixa Ehlers, 1901 | Syllis prolixa | 3477 |
| Palposyllis prosostoma Hartmann-Schröder, 1977 | Palposyllis prosostoma | 3477 |
| Exogone pseudolourei San Martín, 1991 | Exogone pseudolourei | 7866 |
| Autolytus pseudosimplex Augener, 1922 | Autolytus pseudosimplex | 7866 |
| Opisthodonta pterochaeta Southern, 1914 | Streptodonta pterochaeta | 19 |
| Syllis pulchra Berkeley & Berkeley, 1938 | Typosyllis pulchra | 75097 |
| Sphaerosyllis pumila Westheide, 1974 | Sphaerosyllis pumila | 8159 |
| Plakosyllis quadrioculata Perkins, 1981 | Plakosyllis quadrioculata | 7866 |
| Autolytus quinquedecimdentatus Langerhans, 1884 | Myrianida quinquedecimdentata | 19 |
| Streptosyllis reducta Hartmann-Schröder, 1960 | Streptosyllis reducta | 2663 |
| Typosyllis regulata Imajima, 1966 | Typosyllis regulata | 8159 |
| Syllides reishi Dorsey, 1978 | Syllides reishi | 8159 |
| Exogone remanei Storch, 1967 | Exogone remanei | 2663 |
| Typosyllis remanei Hartmann-Schröder, 1960 | Typosyllis remanei | 2663 |
| Sphaerosyllis renaudae Hartmann-Schröder, 1958 | Sphaerosyllis renaudae | 7866 |
| Amblyosyllis rhombeata Grube, 1857 | Amblyosyllis rhombeata | 7866 |
| Sphaerosyllis ridgiensis Blake & Hilbig, 1990 | Sphaerosyllis ridgiensis | 8774 |
| Pionosyllis riojai San Martín, 1990 | Pionosyllis riojai | 7866 |
| Sphaerosyllis riseri Perkins, 1981 | Sphaerosyllis riseri | 7866 |
| Brania robusta Rullier, 1973 | Brania robusta | 3477 |
| Autolytus robustisetus Wu & Sun, 1978 | Autolytus robustisetus | 82601 |
| Exogone rocas Nascimento, Fukuda & Paiva, 2020 | Exogone rocas | 3477 |
| Exogone rolani San Martín, 1991 | Exogone rolani | 7866 |
| Ehlersia rosea Langerhans, 1879 | Syllis rosea | 8159 |
| Ehlersia rosea magna Westheide, 1974 | Syllis magna | 87283 |
| Exogone rostrata Naville, 1933 | Exogone rostrata | 3477 |
| Atelesyllis rubrofasciata Pruvot, 1930 | Atelesyllis rubrofasciata | 3477 |
| Odontosyllis rubrofasciata Grube, 1878 | Odontosyllis rubrofasciata | 2663 |
| Autolytus rubrolineatus Gidholm, 1967 | Autolytus rubrolineatus | 19 |
| Grubeosyllis rugulosa Verrill, 1900 | Grubeosyllis rugulosa | 7866 |
| Typosyllis salina Hartmann-Schröder, 1959 | Typosyllis salina | 8159 |
| Trypanosyllis sanmartini Çinar, 2007 | Trypanosyllis sanmartini | 3477 |
| Syllis sardai San Martín, 1992 | Syllis sardai | 7866 |
| Trypanosyllis savagei Perkins, 1981 | Trypanosyllis savagei | 7866 |
| Autolytus scheremetevskiyi Averincev, 1982 | Autolytus scheremetevskiyi | 3477 |
| Typosyllis schulzi Hartmann-Schröder, 1960 | Syllis schulzi | 3477 |
| Syllis sclerolaema Ehlers, 1901 | Syllis sclerolaema | 3477 |
| Anguillosyllis sepula Maciolek, 2020 | Anguillosyllis sepula | 3477 |
| Pionosyllis serrata Southern, 1914 | Pionosyllis serrata | 19 |
| Pionosyllis serratisetosa López, San Martin & Jiménez, 1997 | Opisthodonta serratisetosa | 86631 |
| Autolytus setoensis Imajima, 1966 | Autolytus setoensis | 82601 |
| Typosyllis setoensis Imajima, 1966 | Typosyllis setoensis | 8159 |
| Parapterosyllis sexoculata Hartmann-Schröder, 1960 | Parapterosyllis sexoculata | 2663 |
| Autolytus simplex Ehlers, 1900 | Autolytus simplex | 3477 |
| Exogone simplex Hartmann-Schröder, 1960 | Exogone simplex | 2663 |
| Pionosyllis singulariseta Russell, 1992 | Pionosyllis singulariseta | 7866 |
| Autolytus smittiae Malaquin, 1883 | Autolytus smittiae | 19 |
| Exogone sorbei San Martín, Ceberio & Aguirrezabalaga, 1996 | Exogone sorbei | 3477 |
| Ambliosyllis speciosa Izuka, 1912 | Ambliosyllis speciosa | 8159 |
| Gattiola spectabilis Johnston in Baird, 1861 | Amblyosyllis spectabilis | 3477 |
| Pionosyllis spinosetosa San Martín, 1990 | Pionosyllis spinosetosa | 7866 |
| Eusyllis spirocirrata Hartmann-Schröder, 1959 | Eusyllis spirocirrata | 8159 |
| Syllis spongicola Grube, 1855 | Haplosyllis spongicola | 75097 |
| Sphaerosyllis sublaevis Ehlers, 1913 | Sphaerosyllis sublaevis | 19 |
| Parapionosyllis subterranea Hartmann-Schröder, 1960 | Parapionosyllis subterranea | 2663 |
| Brania swedmarki Gidholm, 1962 | Salvatoria swedmarki | 19 |
| Anguillosyllis taleola Maciolek, 2020 | Anguillosyllis taleola | 3477 |
| Autolytus tamanus Imajima, 1966 | Autolytus tamanus | 7866 |
| Typosyllis taprobanensis Wiley, 1905 | Typosyllis taprobanensis | 2663 |
| Sphaerosyllis taylori Perkins, 1981 | Sphaerosyllis taylori | 7866 |
| Pionosyllis templadoi San Martín-Peral, 1991 | Pionosyllis templadoi | 7866 |
| Streptosyllis templadoi San Martín, 1984 | Streptosyllis templadoi | 3477 |
| Sphaerosyllis tetralix Eliason, 1920 | Prosphaerosyllis tetralix | 19 |
| Typosyllis tigrinoides Augener, 1922 | Typosyllis tigrinoides | 7866 |
| Syllis torquata Marion & Bobretzky, 1875 | Syllis torquata | 3477 |
| Typosyllis tortugaensis Augener, 1922 | Typosyllis tortugaensis | 7866 |
| Autolytus trilineatus Berkeley & Berkeley, 1945 | Proceraea prismatica | 3477 |
| Anguillosyllis truebloodi Maciolek, 2020 | Anguillosyllis truebloodi | 3477 |
| Perkinsyllis tsilo San Martín, Lucas & Westheide, 2021 | Perkinsyllis tsilo | 3477 |
| Eurysyllis tuberculata Ehlers, 1864 | Eurysyllis tuberculata | 7866 |
| Odontosyllis twincayensis Russell, 1989 | Odontosyllis twincayensis | 7866 |
| Parapionosyllis uebelackerae San Martín, 1991 | Parapionosyllis uebelackerae | 7866 |
| Odontosyllis undecimdonta Imajima & Hartman, 1964 | Odontosyllis undecimdonta | 8159 |
| Pionosyllis uraga Imajima, 1966 | Opisthodonta uraga | 7866 |
| Autolytus usaensis Imajima, 1966 | Epigamia usaensis | 2663 |
| Syllis valida Grube, 1857 | Syllis valida | 3477 |
| Syllis variegata Grube, 1860 | Syllis variegata | 3477 |
| Autolytus varius Treadwell, 1914 | Autolytus varius | 8159 |
| Syllis verruculosa Augener, 1913 | Typosyllis verruculosa | 3477 |
| Parexogone viejoi San Martín, Lucas & Westheide, 2021 | Parexogone viejoi | 3477 |
| Syllis violacea Ehrenberg & Grube, 1869 | Typosyllis violacea | 2663 |
| Syllis vittata Grube, 1840 | Syllis vittata | 3477 |
| Trypanosyllis vittigera Ehlers, 1887 | Trypanosyllis vittigera | 7866 |
| Syllis vivipara Krohn, 1869 | Syllis vivipara | 3477 |
| Typosyllis vivipara Krohn, 1869 | Syllis vivipara | 7866 |
| Pionosyllis weismanni Langerhans, 1879 | Brevicirrosyllis weismanni | 7866 |
| Brania wellfleetensis Pettibone, 1956 | Brania wellfleetensis | 7866 |
| Syllis westheidei San Martín, 1984 | Syllis westheidei | 3477 |
| Exogone wolfi San Martín, 1991 | Exogone wolfi | 7866 |
| Sphaerosyllis xarifae Hartmann-Schröder, 1960 | Prosphaerosyllis xarifae | 2663 |
| Salvatoria ypsiloides Nascimento, Fukuda & Paiva in Nascimento et al., 2021 | Salvatoria ypsiloides | 3477 |
| Autolytus zonatus Mohammad, 1973 | Autolytus zonatus | 2663 |