New genus of falsiformicid wasps (Hymenoptera, Vespoidea: Falsiformicidae) with brachypterous male from middle Cretaceous Kachin amber in Myanmar

Abstract

Falsiformicidae is a poorly known extinct family of aculeate wasps. It is known only as inclusions in various Cretaceous ambers. Brachypterous male Falsiformix pedestris Zhang and Rasnitsyn gen. et sp. nov. is described in the family Falsiformicidae based on a unique fossil from the middle Cretaceous Kachin amber. Occurrence and meaning of the male flightlessness in Hymenoptera is discussed. A combination of the flightless males with flying females occurs when mating takes place shortly after the eclosion, before adults disperse from confined space where they developed. An equally rare even if less exotic strategy with males and females both being flightless depends on the female pedestrian habits rather than on the pre-dispersal mating. Wide spatial (Angara Land, Laurussia Land and Gondwana Land) and narrow temporal distribution (Cenomanian and Turonian ages only) indicate Falsiformicidae as a possibly important stratigraphical indicator.