New mayfly genera from the Middle Triassic of Poland and their evolutionary and paleogeographic implications (Ephemerida: Litophlebiidae, Vogesonymphidae) Author Sinitshenkova, Nina D. Author Aristov, Daniil S. Author Wegierek, Piotr Author Żyła, Dagmara text Zootaxa 2015 3949 2 281 288 journal article 10.11646/zootaxa.3949.2.8 bec6d0a9-b118-471e-aa1e-42c0e6628069 1175-5326 235827 A5F993A6-5E36-47DD-BED5-A407BE159A18 Genus Triassolitophlebia Sinitshenkova & Aristov , gen. nov. Type species. Triassolitophlebia palegica Sinitshenkova & Aristov , sp. nov. , by monotypy. Diagnosis. The forewing is 3.2 times as long as wide, the apex widely rounded. SC does not reach the wing apex. In the RS system, there are not fewer than five longitudinal veins, and RS is not fused with MA stem at the wing base. MA branches in the basal half of the wing, and MP divides at the very wing base. CuA is long and reaches the wing margin distally of MA branching; CuP is long and reaches the wing margin in the basal third of the wing. Comparison. The new genus differs significantly from Litophlebia Riek, 1976 by the long CuA and CuP and by a shorter SC. In the original description of Litophlebia ”RS appearing to arise as a forward branch of MA, in fact on the photo ( Riek 1976: Fig. 3 ) it can be distinctly seen that the basal part of RS stem comes closely to the basal part of MA stem and runs near to it for some distance. Perhaps they are not fused, because at the very wing base the RS base is seen as a fine separate vein. For the Ephemeroptera the separate arising of RS from the wing base is characteristic. Some features of the new mayfly venation have a formal similarity to that of Triassodotes vogesiacus Sinitshenkova & Papier, 2005 ( Sinitshenkova et al. 2005 ) and Tintorina meridensis Krzeminski & Lombardo, 2001 of the family Tintorinidae ( Krzeminski & Lombardo 2001 ) . These features include the short SC and MP branching at the wing base. These are the proper characters that clearly distinguish the Triassic Triassodotes from the Permian Misthodotes Tshernova, 1965 ( Tshernova 1965 ; Kinzelbach & Lutz 1984 ). In spite of this similarity, the new mayfly could not be referred to the Misthodotidae because of the sharp corrugation that is not characteristic for this family but rather typical for the Litophlebiidae . The representatives of the Misthodotidae have wider wings; they are flattened to some extent and never have a sharp corrugation. This feature is also the main difference between the Litophlebiidae and the Tintorinidae . Moreover, the wings of the Tintorinidae are longer and narrower; they are 3.7 times as long as wide. Etymology. The name is a combination of the period – Triassic and Litophlebia – the type genus of the family. Gender: feminine.