Phylogenetic evidence suggests the non-validity of the Iberian land snail genus Tartessiberus and confirms its synonymy with Iberus (Helicidae) Jowers, Michael Joséph Liétor, José Tudela, Antonio R. Jódar, Pedro A. Galán Luque, Inés Moreno Rueda, Gregorio Andalusia Gastropoda Helicidae The monospecific genus Tartessiberus was described in the year 2021 including a single species (T. cilbanus). However, its description relied solely on morphological and anatomical data. In the present work, we use a fraction of the mitochondrial DNA cytochrome oxidase subunit I (COI), 16S ribosomal RNA (16S rRNA) and the nuclear large ribosomal subunit (LSU) to clarify its validity through phylogenetic positioning. Knowledge of the distribution of this species is also improved by citing new locations and expanding the geographical range to approximately 200 km2. Additionally, a morphometric analysis of 259 shells is presented for comparisons with shells of the Iberus marmoratus complex and testing the power of conchological features as a tool for specimen identification. The relatively high conchological variability found for T. cilbanus, together with the discovery of populations with intermediate conchological features between T. cilbanus and other closely related taxa, suggest that the determination of this species should be based on genetic criteria. Our molecular analyses demonstrate that T. cilbanus belongs to the Iberus genus, and thus, we proceed to update its taxonomic status to Iberus cilbanus comb. nov., and, thus, to consider Tartessiberus from now on as a junior synonym of Iberus. 2024-09-06T07:36:45Z 2024-09-06T07:36:45Z 2024-05-14 journal article Jowers MJ, Liétor J, Tudela AR, Jódar PA, Galán-Luque I, Moreno- Rueda G (2024) Phylogenetic evidence suggests the non-validity of the Iberian land snail genus Tartessiberus and confirms its synonymy with Iberus (Helicidae). ZooKeys 1201: 219–231. https://doi.org/10.3897/zookeys.1201.117318 https://hdl.handle.net/10481/94031 10.3897/zookeys.1201.117318 eng info:eu-repo/grantAgreement/EC/H2020/857251 http://creativecommons.org/licenses/by/4.0/ open access Atribución 4.0 Internacional Pensoft