Two new pygmy mole crickets from mid-Cretaceous Kachin amber of northern Myanmar (Orthoptera: Tridactyloidea: Tridactylidae)

Abstract

A new species of Cascogryllus and a new genus of Tridactylidae (pygmy mole crickets) are established based on two specimens from mid-Cretaceous Kachin amber. Amberotridactylus cheni gen. et sp. nov. is mainly characterized by nine-segmented antennae, absence of swimming plates (tibial lamellae) on serrated metatibia, metatarsus slightly longer than apical spurs, and absence of subapical denticular process on metatarsus. Amberotridactylus cheni gen. et sp. nov. is the first representative of the subfamily Tridactylinae from the Mesozoic and the oldest fossil record of this subfamily. Cascogryllus setosus sp. nov. is mainly identified by ten-segmented antennae, prosternum with a prosternal tubercle, curved ScA nearly ending on mid-length of ScP, R present, and almost identical length of paraproctal lobes and cerci. Our findings enrich the biodiversity of pygmy mole crickets in the Cretaceous.