Résumé
A large sample of 65 individuals of the recently described goby Zebrus pallaoroi was collected in France. The species identity of these individuals was confirmed based on morphology. In addition, the species identity was validated through genetic analysis for one of the two specimens collected from the new depth records for the species. The diagnostic characters of Z. pallaoroi, originally based on a limited number of type specimens, were tested on this larger sample and critically analyzed. The diagnostic characters of Z. pallaoroi were revised, and recommendations were made for improving the study of diagnostic characters in gobiid species description, particularly when based on small sample sizes. The record of Z. pallaoroi in the western Mediterranean significantly expands its known geographic range, increases the maximum recorded depth of the species, and reveals syntopic co-occurrence with its phylogenetically closest relatives.