The first Sharephemeridae (Insecta: Ephemeroptera) from the Jurassic Shiti Formation of South China

The new genus and species, Jurassephemera zhangi gen. et sp. nov., belonging to the extinct family Sharephemeridae (Ephemeroptera: Mesephemeroidea), is established from the late Early Jurassic interval of the Shiti Formation of Guangxi Zhuang Autonomous Region, South China. The new genus and species is characterised by its moderate size; small head with reduced compound eyes; body with ten abdominal segments; round-triangular forewing shape; vein R dividing three times, forming five veinlets and three triads; veins MA, MP, and CuA straight, all basally forking once with single triads between; crossveins well developed; and hind wing oval, much smaller than forewing, with veins generally radial and single. SEM observations also reveal that crossveins are much more developed than previously recognised under optical illumination. The forewing venation of all sharephemerid genera is compared. The first report of this family in China herein increases the diversity and palaeogeographic distribution of Sharephemeridae.

Automated summary

This study reports a new genus and species, Jurassephemera zhangi, discovered in Guangxi Zhuang Autonomous Region, China. This extinct genus belongs to the family Sharephemeridae and is characterized by its moderate size and unique wing venation structure. The findings of this study contribute to the understanding of the diversity and paleogeographic distribution of Sharephemeridae in China.