The purpose of this application, under Article 23.9.5 of the Code, is to conserve current usage of the specific name of Choeridium latum Boucomont, 1928, a junior primary homonym of Choeridium latum Blanchard, 1846. These names are currently used as valid in combination with different nominal genera: Blanchard's species with Canthidium Erichson, 1847, to which it was transferred in 1869, and Boucomont's with Ateuchus Weber, 1801, a generic combination that was implicitly established in 1946 but first explicitly used as such only in 2000. These two primary homonyms have never been considered congeneric, and it is highly unlikely that they could ever be. It is proposed that Choeridium latum Boucomont, 1928 be conserved by ruling that it is not invalid by reason of being a junior primary homonym of Choeridium latum Blanchard, 1846.

The purpose of this application, under Article 23.9.3 of the Code, is to conserve the well-used names Propappus Michaelsen, 1905 and Propappidae Coates, 1986 (Annelida) by suppression of the senior homonym Propappus Seeley, 1888 (Reptilia), a junior subjective synonym of Pareiasaurus Owen, 1876.

The purpose of this application, under Article 23.9.3 of the Code, is to conserve the usage of the generic name Ctenarytaina Ferris & Klyver, 1932 for a genus of psyllids (Insecta, Hemiptera) from tropical and subtropical regions around the world. This name, which has been used in hundreds of works in recent decades, is threatened by a purported senior synonym, Eurhinocola Crawford, 1912. This genus was erected for Eurhinocola gravelyi Crawford, 1912 from Myanmar, a species that has not been mentioned since then in the literature except in catalogues. In 2020 the two genera were formally synonymized. Besides those already mentioned, only three other substantial publications on Eurhinocola have appeared, all between 1924 and 1937 and all pertaining to Eurhinocola eucalypti (Maskell, 1890). Using the senior synonym Eurhinocola would lead to nomenclatural instability and confusion, particularly with respect to two economically important species that are classified now in Ctenarytaina. We therefore request a reversal of precedence under the Commission's plenary power, with Ctenarytaina to be given precedence over Eurhinocola whenever the two are considered to be synonyms.

The purpose of this application, under Article 75.6 of the Code, is to conserve the current usage of the name Charopus rotundatus Erichson, 1840 for a species of soft-winged flower beetle from Sardinia and North Africa by setting aside all previous type fixations for this nominal species and designating a neotype. One of the two existing syntypes is in fragmentary condition and the other is not in taxonomic accord with the prevailing usage of the species name because it belongs to another taxon of the same family, Troglops brevis Erichson, 1840. Stability and universality are threatened unless the existing type series for C. rotundatus is set aside and a neotype conforming to the original and current species concept is designated.

The International Commission on Zoological Nomenclature finds no basis under the provisions of the Code for regarding the name Spracklandus as unavailable, nor for regarding any of issues 1–24 of Australasian Journal of Herpetology as being unpublished in the sense of the Code, but the Commission has declined to use its powers to confirm what is obvious. The Commission is not empowered to take Appendix A of the Code (Code of Ethics) into account in its rulings on this or any other Case.

The International Commission on Zoological Nomenclature has declined to use its plenary power to rule on the validity of the specific names of Galago demidoff Fischer, 1806 and Macropus (Galago) demidovii, Fischer, 1808 or to designate neotypes for Galago demidoff Fischer, 1806 and Lemur minutus Cuvier, 1797. As a result, the specific name demidoff Fischer, 1806, as published in the original binomen Galago demidoff remains available from normal application of the Code, and the specific name demidovii Fischer, 1808, as published in the original binomen Macropus (Galago) demidovii remains an unjustified emendation. Neotypes for both Galago demidoff Fischer, 1806 and Lemur minutus Cuvier, 1797 can be designated without application to the Commission by meeting all conditions of Article 75.3 of the Code.

The International Commission on Zoological Nomenclature has conserved current usage of the generic name Bidessus Sharp, 1880 by designating Dytiscus unistriatus Schrank, 1781 as its type species and suppressing Dyticus parvulus Müller, 1776 for the purposes of the Principle of Priority. The International Commission on Zoological Nomenclature has used its specific powers to confirm that authorship of the nominal taxon Dytiscus unistriatus is to be attributed to Schrank, 1781, as the work published by Goeze in 1777 is not consistently binominal and the names proposed in it are, therefore, unavailable (aside from some few that were previously ruled available by the Commission).

The International Commission on Zoological Nomenclature has conserved current usage of the specific name of Curculio antirrhini Paykull, 1800 (currently Rhinusa antirrhini) for a common Palaearctic weevil species by giving this nominal species precedence over its little-used older subjective synonym Curculio noctis Herbst, 1795, whenever the two are considered synonyms.

The International Commission on Zoological Nomenclature has conserved current usage of the specific name of Circus assimilis Jardine & Selby, 1828 for the Australo-Wallacean spotted harrier by designating a neotype for this nominal species. The International Commission on Zoological Nomenclature has also conserved current usage of the specific name of Circus approximans Peale, 1848 by suppressing, for the purposes of the Principle of Priority, its objective synonym Circus juxta Peale, 1848, which was published simultaneously with it but was designated as the senior synonym by the first reviser.

The International Commission on Zoological Nomenclature has conserved current usage of the name of the Late Devonian ammonite genus Costaclymenia Schindewolf, 1920 and, consequently, the family Costaclymeniidae Ruzhencev, 1957 by designating a neotype for the type species of this nominal genus, Goniatites binodosus Münster, 1832.

The International Commission on Zoological Nomenclature has conserved current usage of the specific name of Chrysomela tenebricosa Fabricius, 1775 for a common and widespread species of European bloody-nosed beetle in the genus Timarcha (Chrysomelidae) by giving it precedence over the misinterpreted and unused senior synonym Tenebrio laevigatus Linnaeus, 1767.

In times of increasing easiness to produce publications, attempts have been made to use the Code's requirements for publication to declare controversial works unavailable. I advise against such strategy, because in this day and age, these requirements are very easily met by anybody and their violation very difficult to prove. This is illustrated by one example each from herpetology, ichthyology, and entomology. Contemporary works with controversial taxonomy and available nomenclatural acts are better taken care of by the scientific community and resolved in the long term by prevailing usage rather than trying to declare them unavailable or seeking suppression of such works by the ICZN.