A characteristic, panduriform, large (ca 80 μm in length) diatom was sporadically
detected in the Hungarian rivers in 2021 and 2022. Surirella tientsinensis Skvortzov
emend. Liu was regarded as an Asian endemic species practically from its description
until the second decade of the 21st century. Here we present the first Hungarian occurrence
of the taxon from 2021, which is the second record for Europe, aft er the previously
published Ukrainian data. In 2022 Surirella tientsinensis was detected from two other
Hungarian river sampling localities. Due to the unmistakable outlook of the species,
probably it is a new member of the Hungarian diatom flora, and its parallel occurrences
in some localities within a short time, is noteworthy.