A new genus of setose-winged barklice (Psocodea: Trogiomorpha: Lepidopsocidae) from the Eocene amber of Oise with notes on the biogeography of Thylacellinae

The members of the family Lepidopsocidae (Psocodea: Trogiomorpha) are commonly known as scaly-winged barklice based on the presence of scales on body and wings. Interestingly, the members of the subfamily Thylacellinae, which is the sister group to the remaining members of the family, lack scales and are characterised by densely setose body and wings. We describe the thylacelline Parathylacella oisensis gen. et sp. nov. from the Eocene amber of Oise (France), corresponding to the only known fossil genus of the family. We compare it with the other genera in the subfamily. It shows a similar habitus to the genus Thylacella, and both may be closely related. The description of the new taxon increases the poorly known palaeodiversity of the lepidopsocids. We comment on the putative palaeobiology of this group and discuss new insights into the palaeobiogeography and early diversification of the subfamily Thylacellinae. An association between the thylacelline barklice and Detarieae (Fabaceae: Caesalpinioideae) trees is plausible. The biogeographic distribution might be partially explained by this association, combined with oceanic currents. Studies on Cretaceous lepidopsocids, as well as other Cenozoic specimens, are crucial to understand the evolution of this group over time, and the possible vicariance process.