Two new genera, Vincalaria and Navalicria , with as type species, respectively, Calvinaria bransoni STAINBROOK, 1948 and Navalicria compacta n. sp., are described from the middle and upper parts of the Fransnian. They result from a further restriction of the meaning of the genus Calvinaria STAINBROOK, 1945, started by the author some twenty years ago. Species of Vincalaria n. gen. are encountered in Belgium, in Canada (District of Mackenzie), in the United States of America (States of Iowa, Nevada, and New Mexico), and in various regions of the People's Republic of China (such as the Guizhou Province) and of the USSR (such as the Russian Platform), while those of Navalicria n. gen. are found in Belgium, Canada (Rocky Mountains). Germany and the People's Republic of China (Hunan Province). Once again the precision that can be reached by using well defined rhynchonellid genera for stratigraphic resolution is thus emphasized.