Micromorphological analysis of quadrifid glands of unidentified Utricularia plants (Lentibulariaceae) found in 2019 on a pond shore near the village of Laski, southern Poland, revealed characters intermediate between U. ochroleuca and U. stygia. To resolve the identity of these plants, we applied flow cytometric analysis of genome size, and found that the plants belonged to U. ochroleuca. Micromorphological and genome size analyses of Utricularia plants found at a peat bog near the village of Parowa, southwest Poland, in 2023 revealed them to be exclusively U. ochroleuca. However, an earlier analysis of quadrifid glands of Utricularia plants found at the same locality in 2013, suggested that these plants belonged to U. stygia. Thus most probably U. stygia found in Parowa in 2013 was later replaced by U. ochroleuca. Field studies, along with critical analysis of herbarium and literature data revealed that U. ochroleuca is declining in Poland, probably surviving in no more than 3–5 localities. Therefore, following the IUCN criteria, U. ochroleuca should be assessed as CR (Critically Endangered) and requiring protection by preserving its habitats. Based on genetic, morphological and molecular data provided in the literature, we discuss the taxonomic status of U. ochroleuca and U. stygia.