several hundreds of valid names exist for this genus !!
you may first limit your sample of studied species to a geographical area or to the results of an already existing phylogeny and examine then the diversity of meristics features within it
In case you are dealing with species of 'Barbus' from Morocco, they are now classified in the genera Luciobarbus, Labeobarbus, Enteromius, Carasobarbus and Arabibarbus.
For the species occurring in the region, you may wish to consult the Catalog of Fishes online:
Casal-Lopez, M., S. Perea, A. Yahyaoui and I. Doadrio 2015: Taxonomic review of the genus Luciobarbus Heckel, 1843 (Actinopterygii, Cyprinidae) from northwestern Morocco with the description of three new species. Graellsia v. 71 (no. 2) (art. e027): 1-24.
Doadrio, I., M. Casal-López, S. Perea and A. Yahyaoui 2016: Taxonomy of rheophilic Luciobarbus Heckel, 1842 (Actinopterygii, Cyprinidae) from Morocco with the description of two new species. Graellsia v. 72 (no. 1): e039: 1-17.
Vreven, E. J. W. M. N., T. Musschoot, J. Snoeks and U. K. Schliewen 2016: The African hexaploid Torini (Cypriniformes: Cyprinidae): review of a tumultuous history. Zoological Journal of the Linnean Society: 1-75