Aeolosomatidae Levinsen, 1884 (original description)
Allurus tetraedrus (Savigny, 1826) accepted as Eiseniella tetraedra (Savigny in Cuvier, 1826) (additional source)
Analycus Levinsen, 1884 accepted as Mesenchytraeus Eisen, 1878 (original description)
Analycus armatus Levinsen, 1884 accepted as Mesenchytraeus armatus (Levinsen, 1884) (original description)
Analycus flavus Levinsen, 1884 accepted as Mesenchytraeus flavus (Levinsen, 1884) (original description)
Analycus glandulosus Levinsen, 1884 accepted as Mesenchytraeus glandulosus (Levinsen, 1884) (original description)
Anobothrus Levinsen, 1884 (original description)
Aonides fulgens Levinsen, 1884 accepted as Paraonis fulgens (Levinsen, 1884) (original description)
Apistobranchus Levinsen, 1884 (original description)
Apistobranchus tullbergi (Théel, 1879) (additional source)
Arenicola claparedi Levinsen, 1884 accepted as Abarenicola claparedi (Levinsen, 1884) (original description)
Aricia tullbergi Théel, 1879 accepted as Apistobranchus tullbergi (Théel, 1879) (source of synonymy)
Branchiobdella astaci Odier, 1823 (additional source)
Chaetogaster diaphanus (Gruithuisen, 1828) (additional source)
Chaetogaster limnaei von Baer, 1827 (additional source)
Chaetogastridae Levinsen, 1884 accepted as Naididae Ehrenberg, 1831 (original description)
Chitinopoma Levinsen, 1884 (original description)
Chitinopoma fabricii Levinsen, 1884 accepted as Chitinopoma serrula (Stimpson, 1853) (original description)
Clitellio ater Claparède, 1862 accepted as Hemitubifex benedii (d'Udekem, 1855) accepted as Tubificoides benedii (d'Udekem, 1855) (additional source)
Clymene praetermissa (Malmgren, 1865) accepted as Praxillella praetermissa (Malmgren, 1865) (basis of record)
Dero digitata (Müller, 1774) (additional source)
Dero obtusa d'Udekem, 1855 (additional source)
Enchytraeus affinis Levinsen, 1884 (original description)
Enchytraeus appendiculatus Buchholz, 1863 accepted as Buchholzia appendiculata (Buchholz, 1863) (additional source)
Enchytraeus bisetosus Levinsen, 1884 accepted as Fridericia bisetosa (Levinsen, 1884) (original description)
Enchytraeus buchholzi Vejdovský, 1878 (additional source)
Enchytraeus durus (Eisen, 1878) accepted as Fridericia dura (Eisen, 1878) (additional source)
Enchytraeus fucorum Levinsen, 1884 accepted as Enchytraeus humicultor Vejdovský, 1879 accepted as Enchytraeus albidus Henle, 1837 (original description)
Enchytraeus galba Hoffmeister, 1843 accepted as Fridericia galba (Hoffmeister, 1843) (additional source)
Enchytraeus leptodera Vejdovský, 1879 accepted as Henlea nasuta (Eisen, 1878) (additional source)
Enchytraeus perrieri Vejdovský, 1878 accepted as Fridericia perrieri (Vejdovský, 1878) (additional source)
Enchytraeus ratzeli Eisen, 1872 accepted as Neoenchytraeus ratzelii (Eisen, 1872) accepted as Fridericia ratzeli (Eisen, 1872) (additional source)
Enchytraeus sordidus Levinsen, 1884 accepted as Enchytraeus humicultor Vejdovský, 1879 accepted as Enchytraeus albidus Henle, 1837 (original description)
Enchytraeus striatus Levinsen, 1884 accepted as Fridericia striata (Levinsen, 1884) (original description)
Enchytraeus ventriculosus d'Udekem, 1854 accepted as Henlea ventriculosa (d'Udekem, 1854) (additional source)
Ereutho Malmgren, 1866 accepted as Polycirrus Grube, 1850 (source of synonymy)
Ereutho smitti Malmgren, 1866 accepted as Polycirrus medusa Grube, 1850 (new combination reference)
Eriographidae Malmgren, 1866 accepted as Myxicolinae Rioja, 1923 (additional source)
Filibranchus Malm, 1874 accepted as Trichobranchus Malmgren, 1866 (source of synonymy)
Filibranchus roseus Malm, 1874 accepted as Trichobranchus roseus (Malm, 1874) (new combination reference)
Glyphanostomum Levinsen, 1884 (original description)
Hemitubifex insignis Eisen, 1879 accepted as Psammoryctides albicola (Michaelsen, 1901) (additional source)
Leucariste smitti (Malmgren, 1866) accepted as Polycirrus medusa Grube, 1850 (new combination reference)
Limnodrilus hoffmeisteri Claparède, 1862 (additional source)
Limnodrilus udekemianus Claparède, 1862 (additional source)
Lumbriculus variegatus (Müller, 1774) (additional source)
Lumbricus boeckii (Eisen, 1874) accepted as Dendrobaena octaedra (Savigny in Cuvier, 1826) (additional source)
Lumbricus eiseni Levinsen, 1884 accepted as Bimastos eiseni (Levinsen, 1884) (original description)
Lumbricus foetidus (Savigny in Cuvier, 1826) accepted as Eisenia fetida (Savigny in Cuvier, 1826) (additional source)
Lumbricus mucosus (Eisen, 1874) accepted as Aporrectodea rosea (Savigny in Cuvier, 1826) (basis of record)
Lumbricus norvegicus (Eisen, 1874) accepted as Allolobophora norvegica Eisen, 1874 (basis of record)
Lumbricus purpureus Eisen, 1871 accepted as Lumbricus castaneus (Savigny in Cuvier, 1826) (additional source)
Lumbricus riparius Hoffmeister, 1843 accepted as Allolobophora chlorotica (Savigny in Cuvier, 1826) (additional source)
Lumbricus rubellus Hoffmeister, 1843 (additional source)
Lumbricus subrubicundus (Eisen, 1874) accepted as Bimastos rubidus (Savigny in Cuvier, 1826) (basis of record)
Lumbricus terrestris Linnaeus, 1758 (additional source)
Lumbricus turgidus Eisen, 1874 accepted as Aporrectodea caliginosa (Savigny in Cuvier, 1826) (basis of record)
Monopylephorus Levinsen, 1884 (original description)
Monopylephorus rubroniveus Levinsen, 1884 (original description)
Nais barbata Müller, 1774 (additional source)
Nais elinguis Müller, 1774 (additional source)
Nais proboscidea Müller, 1774 accepted as Stylaria lacustris (Linnaeus, 1758) (additional source)
Nais serpentina Müller, 1774 accepted as Ophidonais serpentina (Müller, 1774) (additional source)
Nicomachella Levinsen, 1884 accepted as Petaloproctus Quatrefages, 1866 (original description)
Nicomachella tenuis (Théel, 1879) accepted as Petaloproctus tenuis (Théel, 1879) (new combination reference)
Notaulax rectangulatus Levinsen, 1884 accepted as Notaulax rectangulata Levinsen, 1884 (original description)
Pachydrilus fossarum Tauber, 1879 accepted as Lumbricillus fossarum (Tauber, 1879) (additional source)
Pachydrilus minutus (Müller, 1776) accepted as Lumbricillus minutus (Müller, 1776) (additional source)
Pachydrilus profugus (Eisen, 1878) accepted as Lumbricillus profugus (Eisen, 1878) (additional source)
Pachydrilus rivalis Levinsen, 1884 accepted as Lumbricillus rivalis (Levinsen, 1884) (original description)
Phreoryctes menkeanus (Hoffmeister, 1843) accepted as Haplotaxis gordioides (Hartmann in Oken, 1819) (additional source)
Psammobius Levinsen, 1884 accepted as Baltidrilus Timm, 2013 (original description)
Psammobius hyalinus Levinsen, 1884 accepted as Baltidrilus costatus (Claparède, 1863) (original description)
Rhynchelmis limosella Hoffmeister, 1843 represented as Rhynchelmis (Rhynchelmis) limosella Hoffmeister, 1843 (additional source)
Sabella nudicollis Krøyer, 1856 accepted as Notaulax nudicollis (Krøyer, 1856) (new combination reference)
Samytha pallescens Théel, 1879 accepted as Glyphanostomum pallescens (Théel, 1879) (source of synonymy)
Spirorbis granulatus tridentatus Levinsen, 1884 accepted as Spirorbis (Spirorbis) tridentatus Levinsen, 1884 (original description)
Spirorbis morchi Levinsen, 1884 (original description)
Spirorbis spirillum ascendens Levinsen, 1884 (original description)
Spirosperma ferox Eisen, 1879 (additional source)
Trochochaeta Levinsen, 1884 (original description)
Tubifex rivulorum Lamarck, 1816 accepted as Tubifex tubifex (Müller, 1774) (additional source)
Uncinais Levinsen, 1884 (original description)
Uncinais uncinata (Ørsted, 1842) (additional source)

Kattegat for Trochochaeta sarsi Levinsen, 1884 

 Authority

 for Aeolosomatidae Levinsen, 1884

The family Aeolosomatidae was described as new in two occasions. It was originally described by Levinsen (1884: ... [details]

 Depth range

 for Aonides fulgens Levinsen, 1884

Type material captured in the water column, with a pelagic net. [details]

 Description

 for Spirorbis granulatus tridentatus Levinsen, 1884

As a variety of Spirorbis granulatus. The text in full (Latin) is: "Warming captis carinæ late rotundatæ et in ... [details]

 Diagnosis

 for Aonides fulgens Levinsen, 1884

Original diagnosis by Levinsen (1884: 101): ''Gjæller ovale, tilspidsede, kortere end Legemets Bredde, begynde paa ... [details]

 Distribution

 for Aonides fulgens Levinsen, 1884

NE Atlantic: Kattegat. [details]

 Etymology

 for Anobothrus Levinsen, 1884

The derivation of Anobothrus (masculine) was not stated by Levinsen but is a combination of ano- (over, above) or ... [details]

 Etymology

 for Aonides fulgens Levinsen, 1884

The specific epithet fulgens is a Latin adjective meaning 'shining' or 'glittering', and refers to the strong ... [details]

 Etymology

 for Spirorbis morchi Levinsen, 1884

Not stated, but clearly for honoring the well-known biologist Otto Andreas Lowson Mörch (also seen as Mørch when ... [details]

 Etymology

 for Trochochaeta Levinsen, 1884

Not stated but assumed (Pettibone, 1963:309) to be for the stellate or wheel-like appearance of the groups of ... [details]

 Grammatical gender

 for Anobothrus Levinsen, 1884

Masculine. Bothrus as Latinized is masculine. Almost all the adjectival species names are masculine to match. Only ... [details]

 Habitat

 for Aonides fulgens Levinsen, 1884

The species was captured in the water column with a pelagic net during night in August 1883. The specimens were ... [details]

 Spelling

 for Spirorbis granulata (Linnaeus, 1767)

Spirorbis is masculine, therefore the epithet should be 'granulatus'. For example Levinsen (1884) correctly uses ... [details]

 Spelling

 for Spirorbis morchi Levinsen, 1884

Levinsen (1884) used the spelling Mørchi. It is not to be transformed to 'moerchi' as this is not an umlaut, and ... [details]

 Type locality

 for Aonides fulgens Levinsen, 1884

Hellebaek, Denmark, Kattegat, NE Atlantic Ocean (gazetteer estimate 56.069, 12.564), pelagic, captured during the night. [details]

 Type locality

 for Trochochaeta sarsi Levinsen, 1884

stated as collected in Kattegat (sea area between Denmark and Sweden), gazetteer geolocation 56.9283, 11.4281. ... [details]