EN
This paper presents the results of a floristic study focusing on taxa representing the genus Gomphonema in Kobylanka stream, situated ca 30 km NW of Kraków. Species belonging to the genus Gomphonema Ehr. were very frequently observed diatom taxa in the material studied. Amongst 272 diatom taxa recorded in the studied material, 13 belong to this genus. Some of them are widespread and often found in Poland; others such as Gomphonema micropus Kutz. and G. sarcophagus Greg. are rarely or for the first time reported from the Kraków-Częstochowa Upland. G. brebissonii Reichardt, G. lagerheimii A. Cl. and G. parallelistriatum Lange-Bert. and Reichardt are new to the Polish flora. Identification of the diatom flora was based on light (LM) and scanning electron microscopy (SEM). Morphological characters and dimensions of frustules were measured for all taxa reported. Ecological requirements, remarks on distribution, and photographic documentation are also given.