The systematic position of bream, Abramis brama (Linnaeus, 1758) and white (silver) bream, Blicca bjoerkna (Linnaeus, 1758) is still being discussed. This paper presents similarities and differences in the fifth pharyngeal arch of the two species, observed in different stages of development. The arch as well as its pharyngeal teeth are thought to be an important systematic character. Hence, the shape of the arch was examined by analysing the ratio between its width (a) and height (h), as well as by studying characters of the pharyngeal teeth, and especially their formula. Frequency of tooth replacement in prelarvae and larvae was examined by observing the frequency of teeth, present in the tissue surrounding the arch. It was found that the arch width index a/h is different in A. brama and B. bjoerkna and can be used as a criterion for species classification. Teeth placed in two rows characterize the tooth formula in A. brama during a short period of ontogenesis, and part of the adults collected from dam reservoirs. It was found that there is a relationship between the frequency of occurrence of replacement teeth and some characteristic periods of changing tooth formula in A. brama. Pharyngeal teeth in adult fish of the two species are replaced continuously, although at a varying rate. Its maximum was observed in summer and autumn.