Disphyllum hilli TSIEN, 1970, D. grabaui TSIEN, 1970, D. rugosum (WEDEKIND, 1922), D. preslense n.sp. and Peneckiella discrete n.sp. are described in detail and have been mostly collected in beds rich in fasciculate rugose corals, occurring in various areas of Belgium. The material investigated comes mainly from the Palmatolepis transitans and P. punctata conodont Zones, at the transition between the Early and the Middle Frasnian. The rugose corals identified herein allow also interesting regional correlations. Disphyllum hilli, D. grabaui and Macgeea rozkowskae COEN-AUBERT, 1982 are abundant at the base of the Moulin Liénaux Formation on the south side of the Dinant Synclinorium and at the base of the Lustin Formation on the north side of the same structural unit. Disphyllum preslense and D. rugosum are widely distributed in the middle part of the Bovesse Formation on the north side of the Namur Synclinorium, in the middle of the reefal limestones from the lower part of the Lustin Formation and in the middle part of the Pont de la Folle Formation which characterizes the northwestern part of the Dinant Synclinorium. Peneckiella discrete serves locally as basement for the small mounds observed at the top of the Moulin Liénaux Formation. Hexagonaria mirabilis MOENKE, 1954 and Tabulophyllum mcconnelli (WHITEAVES, 1898) are frequently associated at the base of the overlying Grands Breux Formation, at the top of the Pont de la Folle Formation, at the top of the reefal limestones from the Lustin Formation and at the base of the Huccorgne Formation capping the Bovesse Formation.