New mayflies (Insecta: Ephemerida = Ephemeroptera) from the intertrappean deposits of the Tunguska Basin, Siberia

Two new monotypic mayfly genera from Permian-Triassic deposits of the Khungtukun-2 and Khungtukun-4 localities on the Nizhnyaya Tunguska River, Evenkia are described; one, Tunephemera tungussica Sinitshenkova gen. et sp. nov., is based on a wing fragment and assigned to the family Sharephemeridae Sinitshenkova, 2002; and the other, Khungtukunia sibirica Sinitshenkova gen. et sp. nov., is based on nymphs and assigned to the family Vogesonymphidae Sinitshenkova et Papier, 2005. The mayflies described suggest Early Triassic rather than Late Permian age of the deposits.