EN
In material from bird nests in the Kaliningrad area (the Baltic, settlement Rybachiy), the authors determined 7 flea species: Ceratophyllus gallinae (Schrank, 1803); C. garei Rothschild, 1902; C.farreni Rothschild, 1905; C.fringillae (Walker, 1856); C.hirundinis (Curtis, 1926); C. rusticus Wagner, 1903; and C. sciurorum (Schrank, 1781). Their representation on the various hosts is given in Table I. Dominant in nests coming from tree hollows was C. gallinae (99.0%), and in nest on buildings, of Delichon urbica - C. hirundinis (85.6%). In 4 specimens of the genus Ceratophyllus, the authors found striking abnormalities of taxonomically important tergites and sternites on their backs (Figs. 2-4). They are of such a nature as to preclude a reliable determination of the relevant specimens.