Tychobythinus Ganglbauer, 1896: 170 Bythinus ottonis Ganglbauer, 1896 Bythoxenus araneipes Normand, 1930 Ceratobythus Normand, 1932: 15 Bythoxenus monoceros Normand, 1932 On the genera Acanthobythus Normand, 1930 and Ceratobythus Normand, 1932 (Coleoptera: Staphylinidae: Pselaphinae) Besuchet, Claude Cuccodoro, Giulio Sabella, Giorgio Revue suisse de Zoologie 2013 2013-06-30 120 2 271 280 8VS6B Ganglbauer, 1896 Ganglbauer 1896 [151,511,579,603] Insecta Staphylinidae Tychobythinus Animalia Coleoptera 1 272 Arthropoda genus      Tychobythinus Ganglbauer, 1896: 170; typespecies:  Bythinus ottonis Ganglbauer, 1896(subsequent designation).  Acanthobythus Normand, 1930: 163; typespecies:  Bythoxenus araneipes Normand, 1930(monotypy).     Ceratobythus Normand, 1932: 15; typespecies:  Bythoxenus monoceros Normand, 1932(monotypy) syn. nov.  COMMENTS: Normand in 1930 and 1932, described respectively Acanthobythusand  Ceratobythusas new subgenera of  Bythoxenus Motschulsky, 1860. Jeannel (1956)raised Acanthobythusto genus rank, arguing that it was certainly a distinct lineage from both his Anopsibythus Jeannel, 1956(erected to accommodate five anophthalmous Algerian species and presently a synonym of  Tychobythinus) and  Ceratobythus, and « also completely unrelated » to  Bythoxenus. In both, the World catalogue of the genera of Pselaphinae( Newton & Chandler, 1989) and Pselaphinaein the Catalogue of Palaearctic Coleoptera ( Löbl & Besuchet, 2004),  Ceratobythusis listed as a valid while Acanthobythusis a synonym of  Tychobythinus. The latter placement has however never been discussed, neither A. araneipesexplicitly transferred.  Acanthobythusand  Ceratobythusshare with the 89 species-rich Holarctic genus  Tychobythinusthe pronotal and elytral foveal systems, as well as most other external characters, such as the antennal scape much longer than wide, narrowed and flattened at basal third and widest at distal third, the maxillary palpi with segments II and III bearing many prominent tubercles and the apical segment distinctly longer than wide and widest at basal third, and prominent tubercles on the anterior margin of protrochanters and profemora. In fact Acanthobythusand  Ceratobythusdiffer from each other and from members of  Tychobythinusonly by head features. The conformation of their aedeagi also fits within the variation observed in  Tychobythinus. Therefore, we consider that there is no justification to maintain them as distinct genera.