Excellently preserved ostracods from large blocks of the late Callovian (Quenstedtoceras lamberti Zone) black clays occurring within glacial drift near Łuków, eastern Poland, are described. Unlike coeval faunas from other localities in Poland, the Łuków ammonite assemblage exhibits boreal affinities. The ostracod fauna broadly resembles those of the British Isles and northwestern Germany, there are also some similarites to Central Russia and northwestern Poland. Seventeen ostracod species are reported, and Schuleridea (Eoschuleridea) lukoviensis sp. n. is proposed. The ostracod assemblage is dominated by large number of specimens of Nophrecythere and Schuleridea (Eoschuleridea). The ostracods are of late Callovian age as indicated by the presence of Nophrecythere triebeli, Progonocythere callovica and advanced evolutionary forms of Nophrecythere intermedia and Terquemula lutzei. The most probable source of the Łuków clay blocks seems to be from the bed of the Baltic Sea north of Gdańsk.

Key words: Ostracoda, Jurassic, Callovian, taxonomy, zoogeography, Poland.

Ewa Olempska [olempska@twarda.pan. pl] and Janusz Błaszyk, Intstytut Paleobiologii PAN, ul. Twarda 51/55, PL-00-818 Warszawa, Poland.