Phylogenetic relationships within the relict family Eomeropidae (Insecta, Mecoptera) based on the oldest fossil from the Early Jurassic (Sinemurian) of Dorset, southern England

The family Eomeropidae is a peculiar relict family of Mecoptera with a single extant species and, until now, eight known fossil species ranging in age from Middle Jurassic to Palaeogene. The oldest representative of the family, Jurachorista bashkuevi gen. et sp. nov., was collected from a coastal outcrop in Dorset, southern England, and is described herein. It extends the fossil record of Eomeropidae back to the Sinemurian (Early Jurassic; c. 196 Ma) and sheds new light on the phylogenetic relationships and past distribution of the family. Analysis of the wing venation of all known Eomeropidae indicates that Notiothauma reedi, the only living representative, is characterized by the most polymerized wings, while the oldest species, the newly described Jurachorista bashkuevi, has the most reduced venation within the family. Phylogenetic analysis based on wing venation produces a tree with two clades, illustrating the different taxonomic lines within the family.