The first fossil Perilestidae (Odonata: Zygoptera) from mid-Cretaceous Burmese amber

Palaeoperilestes electronicus gen. et sp. nov. is the first perilestid damselfly described from mid-Cretaceous Burmese amber. This new damselfly can be attributed to the family Perilestidae by the midfork being distal of the subnodus and the base of IR2 quite near to the base of RP2, both features found in the extant genera Perilestes and Perissolestes. Palaeoperilestes electronicus gen. et sp. nov. has a strongly zigzagged IR1, however, differing from Perilestes and Perissolestes which have a straight IR1. The discovery not only adds to the diversity of damselflies in Burmese amber, but also puts the origin of Perilestidae back to at least the mid-Cretaceous.     

Electrodysagrion lini gen. et sp. nov., the oldest Dysagrionini (Odonata: Zygoptera: Dysagrionidae) from mid-Cretaceous Burmese amber

The dysagrionid damselflies are relatively diverse in Burmese amber, with two genera already recorded. A new dysagrionid damselfly, Electrodysagrion lini Zheng, Nel and Wang, gen. et sp. nov., corresponding to the oldest record of the tribe Dysagrionini, is described herein. It has the unique ‘sieblosiid-dysagrionine’ type of discoidal cell. It differs from other genera of Dysagrionini in having no antenodal crossveins distal of Ax2, Arc aligned with Ax2, and only one row of cells in the cubito-anal area below the nodus. This find puts the origin of Dysagrionini back to at least the mid-Cretaceous.     

Burmadysagrioninae,a new subfamily (Odonata: Zygoptera: Dysagrionidae) from mid-Cretaceous Burmese amber

A new subfamily, Burmadysagrioninae Zheng, Wang and Nel, subfam. nov., for the genus and species Burmadysagrion zhangi Zheng, Wang and Nel, gen. et sp. nov. is described from mid-Cretaceous Burmese amber. This is the third dysagrionid damselfly from the Mesozoic and the second one from Burmese amber. The new specimen has a unique discoidal cell with the anterior and posterior sides not parallel, and the basal side longer than the distal side, unlike the typical ‘sieblosiid-dysagrionine’ type. It differs from other dysagrionid damselflies by the presence of a simple wing venation, the vein IR1 originating below the pterostigma and a special discoidal cell.     

A new damselfly (Odonata: Zygoptera: Platystictidae) from mid-Cretaceous Burmese amber

The genus Mesosticta Huang, Azar, Cai et Nel, 2015 was established based on the wing bases of two damselflies from mid-Cretaceous Burmese amber. Here we describe a new well-preserved platystictid damselfly, Mesosticta electronica sp. nov., with complete forewings and hindwings. The diagnosis of Mesosticta is revised and augmented in this paper. Mesosticta electronica sp. nov. differs from Mesosticta burmatica Huang, Azar, Cai et Nel, 2015 in having the arculus slightly distal of Ax2, a free subdiscoidal cell, the hindwing AA ending on the middle area of the posterior side of the discoidal cell, and the base of RP2 being three or four cells distal of the subnodus. The new discovery adds to the diversity of damselflies in mid-Cretaceous Burmese amber and puts the origin of Platystictidae to at least the mid-Cretaceous.