Mayfly Ephemeraglaucops (Ephemeroptera, Ephemeridae) recorded in the Czech Republic after almost a century

BACKGROUND: The mayfly Ephemera (Sinephemera) glaucops Pictet, 1843 has been considered regionally extinct in the Czech Republic, with the last occurrence dating from 1933. Its extinction was connected with the anthropogenic changes of lowland rivers, forming the original habitat of E.glaucops within the area of the Czech Republic. However, the species has been reported as spreading in man-made, often post-industrial waterbodies in Germany, The Netherlands and Austria since the 1970s. NEW INFORMATION: We report E.glaucops from the Czech Republic, based on 27 larvae collected in the North Bohemia lignite basin in 2018. All individuals were found at one locality – a small kaolin pit in the shallow part near the shore, mostly without macrophytes. We provide details about the locality and morphological diagnostic characters of E.glaucops. This study highlights the importance of post-industrial sites for aquatic biodiversity as surrogate biotopes for degraded original habitats.