The purpose of this application, under Article 75.5 of the Code, is to conserve the current usage of the generic name Halitherium Kaup, 1838 and the specific name of its type species, Pugmeodon schinzii Kaup, 1838 (currently Halitherium schinzii), for a taxon of fossil sirenian from Europe by designating a neotype for this nominal species. This is in response to a recent contention that, as nomina dubia, these two names are inapplicable to the two sympatric species of this genus purported to occur around the type locality of H. schinzii in the Mainz Basin and elsewhere in Europe. The existing holotype is an isolated premolar that is not unambiguously determinable to species, but the name Halitherium schinzii has been used in a substantial body of literature extending over nearly two centuries, to the near exclusion of other names, and without taxonomic ambiguity because of reference to other specimens than the type. The desired ends can be attained without sacrificing stability of nomenclature by designating the most suitable reference specimen as the neotype of Pugmeodon schinzii Kaup, 1838 under the plenary power and continuing to use the name Kaupitherium bronni (Krauss, 1858), with its own, different name-bearing type, for the other species.

This application has two purposes. The first, under Article 23.9.5 of the Code, is to conserve the specific name of the binomen Helix unidentata Draparnaud, 1805, a junior primary homonym of Helix unidentata Holten, 1802, by ruling that the former is not thereby invalid. These names are currently in use for two different species of stylommatophoran snails that have not been treated as congeneric since 1898. Helix unidentata Draparnaud, 1805 has been considered the type species of Petasina Beck, 1847 (Helicoidea, Hygromiidae,) by a majority of authors, whereas Helix unidentata Holten, 1802 is the valid name of Helix ventricosa De Cristofori & Jan, 1832, the type species of Stylodonta De Cristofori & Jan, 1832 (Acavidae, Rhytidoidea). The second purpose of this application, under Art. 81.1 of the Code, is to clarify the status of Petasina Beck, 1847 by (a) fixing Helix unidentata Draparnaud, 1805 as its type species and (b) confirming that Petasina Beck, 1847 is an available name independent of Petasia Beck, 1837. This is necessary to maintain current usage of not only Petasina Beck, 1847 but also another frequently used genus-group name, Euconulus Reinhardt, 1883 (Euconulidae, Trochomorphoidea). Finally, lectotypes are designated for Helix unidentata Draparnaud, 1805 and Helix edentula Draparnaud, 1805.

The purpose of this application, under Articles 23.9.3, 41, 65.2, and 70.2 of the Code, is to conserve the current usage and year of priority of the name Emplectonematidae Bürger, 1904 for a family of ribbon worms by reversing its precedence with respect to a senior synonym, Eunemertidae Joubin, 1894, and to conserve the current concept and usage of its type genus, Emplectonema Stimpson, 1857, by designating Emplectonema viride Stimpson, 1857 as the type species. In preparation for these rulings, a common type species, Nemertes gracilis Johnston, 1837, is designated herein for the nominal genera Nemertes Johnston, 1837 (a largely neglected junior homonym of Nemertes Cuvier, 1816) and Eunemertes Joubin, 1894, thereby rendering the latter an objective junior synonym of the former and of its valid substitute name. The type species of Nemertes Cuvier, 1816 was excluded from Nemertidae sensu McIntosh, 1874 and sensu Hubrecht, 1879, which, having been recognized as a valid grouping by later authors, required a new name. Of the two available candidates, Eunemertidae Joubin, 1894 has been almost unused since the 1900s, whereas Emplectonematidae Bürger, 1904 has been in universal use since its proposal. The latter name has an uncertain date of priority; 1874, 1894 or 1904, depending on whether and how Art. 40.2 applies to it. Emplectonema viride Stimpson, 1857, or its senior synonym Emplectonema gracile (Johnston, 1837), has universally been regarded as the type species of Emplectonema since the 1950s; however, two overlooked fixations in 1892 and 1893 of Borlasia camillea Quatrefages, 1846 as the type species of this genus now threaten the stability of nemertean genus- and family-level taxonomy.

The purpose of the present application, under Articles 74.1.1 and 81.1 of the Code, is to maintain consistent usage of the commonly used name Emoia nigra (Hombron & Jacquinot, 1853) by setting aside a lectotype designation for Gongylus (Eumeces) freycineti Duméril & Bibron, 1839 by Wells & Wellington in 1985 in favour of a later lectotype designation by Brown in 1991.

There has been, and to some extent remains, confusion over the valid genus name for a group of slugs in the family Veronicellidae, either Vaginulus Férussac, 1822 or Vaginula auctt., often cited as of Berthold, 1827 or sometimes as of Blainville, 1828. We show that Vaginula was first made available as an emendation of Vaginulus Férussac by Hoffman in 1925 (Article 33.2.1 of the Code) and that all previous usages of the name were therefore incorrect subsequent spellings. However, Hoffman's emendation was unjustified (Art. 33.2.3). Vaginulus Férussac is the valid name and Vaginula Hoffman is a junior objective synonym. Vaginula Hoffman is also a junior homonym of Vaginula Risso, 1826 (Protozoa, Foraminifera) and of Vaginula Sowerby, 1833 (Gastropoda, Pteropoda).