Abstract: | The genetic relationships among New and Old World coregonid fishes were studied by electrophoresis. The genetic composition of 60 populations, representing perhaps nine commonly recognized species of Coregonus and Stenodus from Europe and North America was determined for 37 genetic loci. Six distinct genetic groups were evident. The first contained only populations of the inconnu, Stenodus leucichthys (Güldenstadt). The Nei genetic distance between Stenodus and Coregonus was 0.305, a relatively small value as compared to other salmonid inter-generic comparisons. The second genetic grouping contained the Arctic cisco, C. autumnalis (Pallas), the N. American lake cisco, C. artedii Lesueur, and the Irish pollan, C. autumnalis pollan Thompson. These three taxa appear to be conspecific on the basis of genetic distances. The third genetic grouping contained the European whitefish, C. lavaretus (L.), and the N. American lake whitefish, C. clupeaformis (Mitchill). European and lake whitefish may be conspecific. Lake whitefish from northwestern N. America were more closely related to European whitefish (genetic distance 0.038) than to lake whitefish from central N. America (genetic distance 0.098). The fourth group contained the broad whitefish, C. nasus (Pallas), which is perhaps more closely related to the European/lake whitefish groups than other coregonids. The fifth genetic grouping contained only the Asian endemic, C. peled (Gmelin), and the sixth contained the least cisco, C. sardinella Valenciennes, and vendace, C. albula (L.), which also appear to be conspecific. The widespread genetic groupings obtained for ciscoes indicate that they do not constitute a single closely related group within the genus Coregonus. |