The structural microscopic characteristics of six microfacial developments of the Oxfordian−CLower Kimmeridgian at nine localities in the Czestochowa region. The microbiostratigraphy of samples was based on the distribution of cadosinid and stomiosphaerid microfossils in thin-sections. Details of the micropaleontological description of the new species Committosphaera czestochowiensis n. sp. are given.