Some but not all superseded combinations are basionyms, and some basionyms are not superseded combinations.[6] The superseded combination is not the same as a synonym and technically should not be called one.[4]
If the species is moved again to a third genus, both of the older names are considered superseded combinations. The original name is the superseded original combination and the second name is the superseded recombination.[4] If the species were moved back to a previous genus, the International Commission on Zoological Nomenclature would not consider the current name to be a new combination.[7]
The specific epithet is kept in all these name changes,[3] with perhaps some modification of the suffix to harmonize with the genus name.
For example, in 1766 Peter Simon Pallas described a new species of marine polychaete worm he called Aphrodita flava.[8] In 1867, that name became a superseded (original) combination when Hjalmar Kinberg moved the species to Thesmia, creating the new combination Thesmia flava.[9] The genus Thesmia was later synonymized with Chloeia,[10] creating a new combination of Chloeia flava[11]Aphrodita flava is the superseded original combination, Thesmia flava is the superseded subsequent recombination, and the current name Chloeia flava is the new combination.[11]
^"Ibatia ganglinosa (Vell.) Morillo". The International Plant Names Index and World Checklist of Vascular Plants 2024. Archived from the original on 18 April 2024. Retrieved 9 July 2024.
^ abMinelli, Alessandro (21 August 2019). "The galaxy of the non-Linnaean nomenclature". History and Philosophy of the Life Sciences. 41 (31): 31. doi:10.1007/s40656-019-0271-0. ISSN1742-6316. OCLC8207041585. PMID31435827. Archived from the original on 18 January 2024. Retrieved 8 July 2024. Soon thereafter, Brünnich (1772) introduced the genus Tapirus and the valid name for the Brazilian tapir is since the Tapirus terrestris and Linnaeus' original binomen (H. terrestris) is reduced to a superseded combination (a combination of the same specific epithet—terrestris, in this case—with the name of a genus to which the species is no longer referred).
^"GLOSSARY DEFINITIONS OF TERMS USED IN THIS CODE". International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) adopted by the Nineteenth International Botanical Congress Shenzhen, China, July 2017. 2018. Archived from the original on 22 March 2023. Retrieved 8 July 2024. new combination (combinatio nova). A new name for a taxon below the rank of genus based on a legitimate, previously published name, which is its basionym and which provides the final epithet of the new combination (Art. 6.10 and 7.3)
^"GLOSSARY DEFINITIONS OF TERMS USED IN THIS CODE". International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) adopted by the Nineteenth International Botanical Congress Shenzhen, China, July 2017. 2018. Archived from the original on 22 March 2023. Retrieved 8 July 2024. basionym. The legitimate, previously published name on which a new combination or name at new rank is based. The basionym does not itself have a basionym; it provides the final epithet, name, or stem of the new combination or name at new rank (Art. 6.10)
^Pallas, P.S. (1766) Miscellanea zoologica. Quibus novae imprimis atque obscurae animalium species describuntur et observationibus iconibusque illustrantur. Petrum van Cleef. Hagí Comitum., xii + 224 pp.;14 pls., available online at https://archive.org/details/pspallasmedicina00pall page(s): 97, plate 8, figures 7-11; note: Indian Ocean (2 locations)