Evolutionary implications of new Postopsyllidiidae from mid-Cretaceous amber from Burma and sternorrhynchan nymphal conservatism

Nymphs of extinct sternorrhynchan hemipterans are extremely scarce, however very important for understanding of evolutionary trait of these insects. A protopsyllidioid nymph, placed in the family Postopsyllidiidae is the first found in the fossil record, based on an inclusion in mid-Cretaceous amber from Kachin, Burma. Postopsyllidiidae so far comprised the sole genus Postopsyllidium with a few species: P. rebeccae , P. grimaldii and P. burmaticum from Kachin amber (Cenomanian) and P. emilyae from Turonian amber of New Jersey. Here we are reporting a new genus and species of the postopsyllid Megalophthallidion burmapteron gen. et sp. nov. (imago) and first known nymph of the family ascribed to the same genus. An overview of fossil record of sternorrhynchan nymphs and their evolutionary implications are presented. This finding unlocked new and complementary window to understanding the evolutionary traits of Protopsyllidioidea and other Sternorrhyncha hemipterans.