A highly diverse coenagrionoid damselfly group (Odonata: Zygoptera: Burmacoenagrionidae fam. nov.) from mid-Cretaceous Burmese amber

Abstract

The damselfly superfamily Coenagrionoidea is the largest zygopteran group, comprising three-fifths of all extant damselfly species. The Mesozoic fossil record of this superfamily is sparse, whilst it is relatively common in Burmese amber. A new coenagrionoid family, Burmacoenagrionidae Zheng et al., fam. nov., is established here based on four new species in three new genera: Burmacoenagrion pretiosus Zheng et al. gen. et sp. nov., Burmachistigma cheni Zheng et al. gen. et sp. nov., Electrocoenagrion elongatum Zheng et al. gen. et sp. nov. and Electrocoenagrion forficatum Zheng et al. gen. et sp. nov. The previously described damselfly genus, Burmagrion Möstel et al., 2017, is transferred to this family. Burmacoenagrionidae Zheng et al. fam. nov. has a long pterostigma covering 3–5 cells, pigmented wings and a sigmoidally curved RA and RP1 distal of the pterostigma, differing from other coenagrionoid damselflies. Until now, this is the most diverse damselfly family reported from Burmese amber, showing that the Coenagrionoidea were already highly diversified 100 million years ago.