A new genus and a new species of Behningiidae from China contributing new insights to the evolution of the family (Insecta: Ephemeroptera)

Although the nymphal morphology of the single known species of the family Behningiidae from China, Behningia nujiangensis Zhou & Bisset, 2019, has been described twice, its phylogenetic position has not been discussed. In this study, we describe a new species, Behningia sushii sp. nov., collected from the middle Yangtze River and Hanjiang River of central China, based on both imaginal and nymphal specimens. This species exhibits distinctive mandibles, labia and hindtarsi. Comparison of those two species and other known species reveals that the B. nujiangensis represents a distinct clade and requires a different generic position. Therefore, we establish a new genus, Paradolania gen. nov., to accommodate it. Links and differences between the four known genera of Behningiidae are also provided. In addition, we propose an Ephemeridae-like ancestor and a Laurasian origin of this family.