Aeolosomatidae Levinsen, 1884 (original description)
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)
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)
Clymene praetermissa (Malmgren, 1865) accepted as Praxillella praetermissa (Malmgren, 1865) (basis of record)
Enchytraeus affinis Levinsen, 1884 (original description)
Enchytraeus bisetosus Levinsen, 1884 accepted as Fridericia bisetosa (Levinsen, 1884) (original description)
Enchytraeus fucorum Levinsen, 1884 accepted as Enchytraeus humicultor Vejdovský, 1879 accepted as Enchytraeus albidus Henle, 1837 (original description)
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)
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)
Leucariste smitti (Malmgren, 1866) accepted as Polycirrus medusa Grube, 1850 (new combination reference)
Lumbricus eiseni Levinsen, 1884 accepted as Bimastos eiseni (Levinsen, 1884) (original description)
Monopylephorus Levinsen, 1884 (original description)
Monopylephorus rubroniveus Levinsen, 1884 (original description)
Notaulax rectangulatus Levinsen, 1884 accepted as Notaulax rectangulata Levinsen, 1884 (original description)
Pachydrilus rivalis Levinsen, 1884 accepted as Lumbricillus rivalis (Levinsen, 1884) (original description)
Psammobius Levinsen, 1884 accepted as Baltidrilus Timm, 2013 (original description)
Psammobius hyalinus Levinsen, 1884 accepted as Baltidrilus costatus (Claparède, 1863) (original description)
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)
Trochochaeta Levinsen, 1884 (original description)
Uncinais Levinsen, 1884 (original description)

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 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]

 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]