Acentria ephemerella ([Denis & Schiffermüller], 1775)
63.1150 (B&F: 1331)
Acentria nivea (Olivier, 1791)
A resident species. Often common to very common and occasionally abundant flying over ponds, dykes and lakes. Widespread. This species is single-brooded flying mainly from late May to mid September, occasionally from the second week of May or to the third week of September. Larvae feed on Canadian waterweed, pondweed, stoneworts and filamentous algae. (Pratt, 2011).